Rolex Caliber & Movement Reference
Main Page -> Movements
Quick jump
| Prince (shaped): 300 · 7½ T.S. 300 · 310 · 360 HW · 350 T.S. |
| Bubbleback / early automatic: 520 · 620 · 600 · A260 · A296 · 645 · 740 · 745 |
| Oyster / Oysterdate Precision: 1210 · 1215 · 1220 · 1225 |
| Vintage sport (1950s–80s): 1030 · 1035 · 1530 · 1560 · 1570 · 1575 |
| Modern sport (1988–2020): 3035 · 3130 · 3135 · 3185 · 3186 · 3187 |
| Milgauss: 1580 · 3131 |
| Daytona chronograph: 72 · 727 · 4030 · 4130 |
| Day-Date: 1055 · 1555 · 1566 · 3055 · 3155 |
| Oysterquartz: 5035 · 5055 |
Rolex movements
Every caliber below powered a reference documented on this wiki. Each gets its own entry: specification woven into the history rather than boxed off in a table, the visual and finishing details that let a collector recognize a genuine example, and a photograph where one has been sourced and verified. Fitment is kept to a representative reference or two rather than an exhaustive list — the individual reference pages carry the full case-by-case detail.
The caliber number is engraved on the movement itself and read with the caseback off; it is separate from the case serial, which is the number that dates the watch on the serial-number page. Where a movement number and case number diverge sharply, as on the stockpiled Prince calibers, the movement was made well before the case it sits in.
Nearly every mechanical Rolex movement on this page, from the earliest Prince calibers through the modern in-house automatics, was physically manufactured by Aegler in Bienne — Rolex's own supplier and, from 2004, its own subsidiary. Two component technologies recur across dozens of the calibers below and are worth understanding once rather than re-explained each time. Glucydur balances, standard on Rolex automatics from the 1930s onward, are a beryllium-bronze alloy — the name fuses "glucinium" (an old name for beryllium) with "dur" for hard — chosen because the alloy resists magnetism and temperature-driven rate variation far better than the steel balances it replaced. Kif shock protection, from the Vallée de Joux firm founded in 1944, cushions the balance staff pivots against impact with a spring-loaded free-bearing jewel setting; Rolex's "Kif Ultraflex" and "Kif Elastor" are Rolex-specific tunings of the same underlying system, not distinct technologies. Parachrom is Rolex's own invention: a niobium-zirconium-oxygen hairspring alloy the company designed and manufactures in-house, introduced from 2000 and distinguished by its blue oxide coating from around 2005, roughly ten times more resistant to shock and largely immune to magnetic fields and temperature swings compared to the Nivarox alloys it replaced.
Prince (shaped movements)
The Prince family runs on Aegler shaped movements, older than every other Rolex caliber on this page. Wilsdorf and Aegler patented the layout in 1927: a "shaped watch movement with a seconds dial" that put the winding barrel at one end of the rectangular movement and the balance at the other. That separation is why Prince movements could carry a larger balance wheel than rival shaped calibers of the period, and a bigger mainspring barrel too — better precision, longer reserve, both from the same design choice.
Aegler made these movements as a supplier, not a Rolex subsidiary. The firm ran independently out of Bienne until Rolex bought it from the Borer family in April 2004. "Aegler" and "Rebberg" refer to the same company — Aegler is the name, Rebberg the street in Bienne where it stood. Aegler also built movements for Gruen, and the architectural sibling of Cal. 300 shipped in the US as the Techni-Quadron under Gruen's own Cal. 877 designation. That shared supplier explains a documented transplant pattern: a Gruen-stamped movement turns up inside a Rolex Prince case now and then. It also explains a real misattribution in the literature — "Cal. 877" occasionally gets listed as a Prince caliber, when it was never a Rolex number at all.
Movement grading across the family runs Prima → Extra Prima → Ultra Prima, rising through jewel count, adjustment positions, and chronometer testing rigour. A "Chronometer" or "Observatory" mark on a Prince dial corresponds to Extra Prima or Ultra Prima grade only — a Prima movement never earns it. Rolex submitted Prince movements to the National Physical Laboratory at Kew for rate certificates independent of the Swiss Bureaux Officiels Suisse de Contrôle; the 1914 Class A Kew certificate Rolex commonly cites as its first official chronometer rating belongs to an earlier ladies' wristwatch movement, predating the Prince family, though the Princes continue that Kew-Teddington testing tradition from 1928 forward.
Cal. 300
| detail | value |
|---|---|
| type | Manual |
| jewels | 15 (Prima) · 18 (Extra/Ultra Prima) |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | ~50h |
| size | 7½ × 14½ lignes / 16.9 × 32.7mm |
| escapement | Lateral lever |
| shock | None |
Cal. 300 is the original Prince movement, 1928 to 1935. Rolex's own factory caliber table lists it under size code "T.S.," the same code shared by Cal. 310 and Cal. 350 below — Christie's calls all three "the same movement base," with parts interchangeable between them and only the balance bridge marking which of the three a given example started as. Grading ran Prima (15 jewels, 6-position) through Extra Prima and Ultra Prima (18 jewels, 6-position, some marked Chronometer); researcher David Boettcher's patent work identifies the three extra jewels precisely — two end-stones on the escape-wheel pivots and one top bearing on the centre wheel. Grade wording moved from the ratchet wheel on early production to the main train bridge later on, itself a rough dating tool. The photographed example, an Extra Prima marked "Observatory 6 Positions," shows the later bridge-stamped convention.
The balance metallurgy shifted over the run: 1928 examples carry a bimetallic balance with a plain Breguet spring, and by the mid-to-late 1930s Antiquorum lots show both monometallic and bimetallic balances paired with Elinvar-alloy hairsprings — a real transition, but a gradual and overlapping one that the auction record never pins to an exact year. "Patented Superbalance," stamped on later ratchet wheels and bridges, refers to Swiss patent CH196706, filed by Aegler — not Rolex directly — in August 1936 and granted March 1938; a movement so marked postdates that grant. The recessed timing screws are often explained as reducing air resistance, but Boettcher argues the patent's real purpose is maximizing the balance's radius of gyration within a small movement, since a plain-rimmed balance can't grow as large in the same footprint. Cal. 300 carries no shock protection, a systematic absence across roughly fifteen Antiquorum Prince lot descriptions spanning 1989 to 2022 — a catalogue style that names shock-absorbers when they're present — consistent with Incabloc only reaching production in 1938, after the Prince's core design was already set. The winding-stem bridge is Cal. 300's known service fail point: a Prince that sets the time and then immediately disengages points to a broken bridge, not a deeper fault, and aftermarket CNC-machined brass replacement bridges and stems circulate among watchmakers as a routine repair part.
UK auction houses have separately catalogued a cluster of three- and four-digit numbers on 1862, 1490, and 1855 movements — 510, 579, 841, 1004, 1130, and 1439, confirmed against specific Bonhams, Christie's, and Tajan lots below, plus a weaker sighting of 701 and a single-sourced 1759. Whether these track distinct Aegler grading tiers or are simply how UK cataloguers transcribe the grade and jewel count stamped on a given movement is unresolved in the record — continental houses (Antiquorum, Christie's Geneva) describe the same class of movement by grade name and the T.S. size code, never by these numbers. Two further numbers sometimes listed alongside them, Cal. 414 and Cal. 527, do not appear in any auction house, dealer, or catalogue record found for the Rolex Prince and are not documented here. A separate case reference, 971A, is sometimes mistaken for a caliber number in secondary listings — the actual movement inside a 971A case is this same T.S./300-family caliber, per Antiquorum's own 1989 cataloguing of one.
Cal. 7½′′′ T.S. 300
| detail | value |
|---|---|
| type | Manual |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | ~50h |
| size | 7½′′′ rectangular |
"T.S." is Rolex's own size-family code for this 16.9 × 32.7mm architecture, printed directly by Christie's as "cal. T.S. Ref. 300" — not, as sometimes assumed, an abbreviation for "Très Soigné"; no source found supports that reading. The Ultra Prima 6-position execution built on this base runs 1932 to 1938: lateral lever escapement, monometallic balance on a micrometer regulator, Breguet overcoil hairspring, rhodium plating. It is documented on the 1527 Railway, where the grade mix inverts the pattern seen on the 1490 — Extra Prima dominates the surviving 1527 population, and an 8-position "Officially Tested in Eight Ways" Ultra Prima example is the outlier at the top of the range, the highest-hammering Prince movement recorded (Mondani 2006, bamboo-bracelet 1931 example, CHF 27,140).
Cal. 310
| detail | value |
|---|---|
| type | Manual |
| jewels | 18 |
| size | 7½′′′ rectangular (19 × 49mm cased) |
The centre-seconds member of the T.S. family, built for the wedge-shaped 3361 Aerodynamic / 3362 / 3937 Prince group. Antiquorum's own Hong Kong 2000 cataloguing of a 3361 gives it directly: "7 1/2′′′, rhodium plated, 18 jewels, lateral lever escapement, Superbalance balance adjusted to 6 positions, self-compensating Breguet balance-spring, micrometer regulator," 19 × 49mm cased. Antiquorum never prints the number "310" itself in that description — the caliber-number attribution to specific serial examples rests on dealer listings rather than the auction house's own text, worth flagging as weaker than the architecture description around it. Production ended in 1938, but Aegler kept stockpiling movements that Rolex cased into 3361 production through 1952; a 1952-cased example with a movement number far lower than its case number is the stockpile pattern showing up directly in the serial record.
Cal. 360 HW
| detail | value |
|---|---|
| type | Manual |
| jewels | 15–18 |
Sources disagree sharply on this caliber, and both readings are printed here rather than picking one. Christie's cataloguing of a 1938 ref. 2835 "Prince Elegant" gives a tonneau-shaped 15-jewel movement, and collector-book author Charles Jarman describes Cal. 360 as "manually wound, small seconds register, tonneau shaped, with a Superbalance" — the reading behind this page's earlier framing of it as a 1936-onward tonneau-plate successor to Cal. 300, used as a visual dating tell on 971, 1490, 1862, and 3361 cases. Against that, a Rolex factory caliber table lists Cal. 360 as rectangle-shaped, 18 × 27mm — a size class well below the 300 family's 16.9 × 32.7mm — 18 jewels, dated 1937, and marked as its own "Basic Caliber" rather than a 300 derivative. The nickname "HW," popularly explained as Hans Wilsdorf's initials, rests on a single dealer source; the same factory table instead shows a size code that reads as "F-LW" in that document, plausibly an OCR artifact of the same "F" size family that also produces Cal. 180's "F." code — the founder-initials story has no independent support and the size-code reading fits the table's own naming pattern better.
Cal. 510
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
Documented on the Prince Brancard ref. 1855, catalogued as a "17-jewel Cal.510 manual wind movement tested to 8 positions" — the same unusual 8-position adjustment seen on Cal. 1004 below, against the more typical 6-position Prima/Extra Prima/Ultra Prima standard.
Cal. 579
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
Bonhams London catalogued a stainless steel ref. 1862, circa 1935, case No. 103, directly as a "17-jewel Cal.579 manual wind movement" — single-sourced to that one lot. Earlier listings of this number carried a trailing "T," which does not appear in Bonhams' own description; the letter is an aggregator-database artifact rather than Rolex or Aegler terminology, and is dropped here.
Cal. 701
| detail | value |
|---|---|
| type | Manual |
The weakest of the numbers on this page: a UK dealer's photograph shows "ROLEX PRINCE 701" legible on a 1930s piece, but no accompanying jewel count, adjustment count, or any other technical description has surfaced anywhere. The marking is real; nothing beyond it is currently documented.
Cal. 841
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 (Bonhams) / 15 (one auction listing) |
Bonhams London, ref. 1862 circa 1930, case No. 10403: "17-jewel Cal.841 manual wind." The same number resold through Tajan in 2019 as "17-jewel Cal.841 manual wind" on the identical watch — one example catalogued twice, not two independent sightings. A separate, smaller consignor listing gives 15 jewels for a "Cal. 841T" on a different 1862, a contradiction worth keeping rather than resolving. As with Cal. 579, the trailing "T" seen in some listings traces to an aggregator database field, not the original auction-house text.
Cal. 1004
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
Bonhams London, 18K two-colour gold bracelet ref. 1862, Glasgow import mark 1936: "17-jewel Cal.1004 manual wind movement tested to 8 positions" — the same 8-position outlier seen on Cal. 510, against the usual 6-position standard.
Cal. 1130
| detail | value |
|---|---|
| type | Manual |
| jewels | 16 |
Documented on a 9K yellow gold ref. 1490, case 30280, catalogued as a "cal. 1130 manual winding lever movement, 16 jewels" — the lowest jewel count recorded for a numbered Prince movement on this page.
Cal. 1439
| detail | value |
|---|---|
| type | Manual |
| jewels | 18 |
Bonhams, Prince Chronometre ref. 1490, Glasgow import mark 1937: "18-jewel Cal.1439 manual wind movement timed to 6 positions" — back to the standard 6-position count after the 510/1004 outliers.
Cal. 1759
| detail | value |
|---|---|
| type | Manual |
| jewels | 18 |
The Ultra Prima Chronometer execution, circa 1937: 18 jewels, 6-position adjustment, documented at Gardiner Houlgate on a 9ct ref. 1862 with Glasgow import hallmarks for 1937, catalogued directly as "cal. 1759 Ultra Prima Chronometer 18 jewel movement timed 6 positions." The photographed example pairs the movement with its original case back, engraved "1759, 18 Rubies, Ultra Prima" alongside "31 Records Universels" and the retailer stamp — a rare survival of movement and original case together. Gardiner Houlgate is a regional UK specialist house rather than one of the major auction rooms, and this number is currently single-sourced to that one lot.
Cal. 350 T.S.
| detail | value |
|---|---|
| type | Manual |
| jewels | 18 |
| size | 16.9 × 32.7mm (T.S.) |
The jump-hour member of the T.S. family, alongside Cal. 300 (small seconds) and Cal. 310 (centre seconds) above. Christie's Geneva (14 May 2018, lot 113) and Sotheby's Geneva (November 2016, lot 135) both catalogue it in the 1491 Brancard Jumping Hour: an 18-jewel, chronometer-rated movement on the T.S. base, in the 1491's rectangular case. Watch Wiki notes the jump-hour disc mechanism works on much the same principle the Datejust's date disc would decades later — an early instance of a mechanism Rolex returned to on a completely different watch. Surviving examples carry Glasgow import hallmarks from 1930-31, consistent with the shared T.S. base's own 1928-35 production window.
Two further notes apply across the whole family rather than to one caliber. The 1491 case runs deeper than the 1490's to house the jump-hour module — that case-depth difference is the canonical way to catch a 1490 retrofitted with a later module and passed off as a genuine 1491. Three module-specific service patterns turn up in the collector record: a weak jump-impulse spring producing a "lazy" disc advance, a worn disc-retention pawl producing hour-disc jitter, and a misaligned dial aperture that reveals fragments of two numerals at once.
Bubbleback and early automatic
Bubbleback and early Oyster Perpetual references run on a distinct family of early self-winding calibers, separate from the Prince's manual shaped movements and predating the standardized post-war automatic line. The "bubble" in Bubbleback describes the domed caseback these movements needed to clear their automatic rotor — a genuine self-winding mechanism, not a bumper system, at a time when most competing automatics still used one.
Cal. 520
| detail | value |
|---|---|
| type | Automatic |
| jewels | 19 |
| frequency | 18,000 vph (2.5 Hz) |
The first Bubbleback caliber, debuting in the original 1933 reference 1858 with its three-piece Oyster case: automatic, 19 jewels, 18,000 vph. Documented on the 3353 by case description. Superseded by Cal. 620 as the movement architecture matured through the mid-1930s. No individually-confirmed movement photograph has surfaced for this caliber yet — treat any generic "early Bubbleback movement" image with a 520 label with caution unless the caliber number is visible engraved on the piece.
Cal. 620
| detail | value |
|---|---|
| type | Automatic |
| jewels | 17 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 35h |
| size | 11½ lignes / 26.4mm × 7.5mm |
11½ lignes, 26.4mm diameter, 7.5mm height, 17 jewels, 18,000 vph, 35 hours of reserve, derived from the manual-wind Cal. 600. The rotor is the defining feature: a uni-directional "Perpetual" weight that spins a full 360 degrees with no bumpers or buffers, at a time when competing automatics still relied on bumper systems. It's engraved "ROLEX PERPETUAL / CHRONOMETER / SWISS MADE / PATENTED / SUPER-BALANCE," and an 18mm cover plate held by three screws carries its own "VIS TIRETTE / PATENTED / TRIGGER SCREW" marking. Cal. 620 powered the original 1931 "Perpetual" and the early Bubbleback generation, and is the base architecture Cal. 630 (and the related 635, 645) evolved from directly.
Cal. 630
| detail | value |
|---|---|
| type | Automatic |
| jewels | 17 |
| frequency | 18,000 vph (2.5 Hz) |
| size | 26.0mm |
Launched 1937, 26.0mm, 17 jewels (Grail Watch Wiki gives 17; WatchGuys lists 18 for the same caliber, a documented count discrepancy between sources), COSC-certified, adjusted to 7 positions, Breguet hairspring. Evolved directly from the Cal. 620 base (Caliber Corner groups 620, 630, 635, and 645 as one related family), and shares its predecessor's cover-plate marking: "Vis Tirette *** Patented *** Trigger Screw." The rotor and bridge carry the same "Rolex Perpetual Chronometer, Swiss Made, Patented, Super-Balance" signature as the 620, which makes the two easy to mix up without checking the caliber number stamped in the small box on the bridge itself.
Cal. 10½ Hunter
| detail | value |
|---|---|
| type | Manual |
| jewels | 15–17 |
| frequency | 18,000 vph (2.5 Hz) |
| size | 10½ lignes |
An Aegler-supplied 10½-ligne hand-wound family (700 / 710 / 720 base architecture) rather than an automatic: 15 jewels early, 17 later, 18,000 vph, non-chronometer, central seconds. It powers the originating Air-King 4925 and its Air-Lion / Air-Tiger / Air-Giant siblings — the 4365 sub-seconds, 4444 mid-size, and 4647 Hunter Precision — through 1945–53, sitting architecturally between the pre-war Prince and Bubbleback shaped calibers and the post-war 1030 automatic.
Cal. 600
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
| size | 9¾ lignes / 21.7mm |
A 9¾-ligne manual caliber, one size class below the 10½-ligne 700/710/720 family above, fitted with a patented Super Balance. Sotheby's November 2025 sale of the Mercedes Gleitze Oyster ($1.73 million, via Robb Report) catalogues the movement as a Hunter-architecture base upgraded to Cal. 600, rhodium-finished, in a 27mm case made in late 1926 — the watch Gleitze wore on her 21 October 1927 Channel swim attempt, caseback engraved "Miss M. Gleitze / The Companion 'Oyster.' Vindication Channel Swim. October 21st. 1927."
Cal. A260
| detail | value |
|---|---|
| type | Automatic |
| jewels | 19 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 36h |
| size | 26.4mm |
1953–55, 19 jewels, 18,000 vph, 36 hours of reserve, 26.4mm — the caliber in the first Submariner references, 6204 and 6205. Its rotor is "non-butterfly," visually distinct from the butterfly-rotor Cal. 1030 that follows it. Hodinkee describes A260 as repurposed from earlier Oyster Perpetual models including later Bubblebacks, rather than a clean-sheet design for the Submariner.
Cal. A296
| detail | value |
|---|---|
| type | Automatic |
| jewels | 18 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 36h |
| size | 29.5mm |
1952–55, 18 jewels, 18,000 vph, 36 hours, 29.5mm, a full-rotor uni-directional Perpetual, not a bumper caliber despite sometimes being described as one — a confusion with Bubbleback-era geometry. A296 powers the Big Crown 6200 and the earliest Explorers (6098, 6150 "Precision," 6298, 6350), and the earliest Datejusts, 6104 and 6105, with the 6150 and 6350 showing the identical movement in non-COSC and COSC form. Some auction and dealer listings write "Cal. 775" instead of "Cal. A296" for the same movement on the same watches — A.296 is Rolex's size-family code and 775 the commercial number, not two different calibers. Cal. 1030 succeeds it from 1955 with bidirectional winding via a butterfly rotor and a thinner autowind module; that thickness reduction is specifically what eliminates the domed Bubbleback caseback profile going forward — Phillips' Geneva Watch Auction FOUR framed the A296-to-1030 swap explicitly as a thickness change, not a different winding concept.
Cal. 645
| detail | value |
|---|---|
| type | Automatic |
| jewels | 17–20 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 41h |
| size | 26.4mm |
A sibling of Cal. 630 sharing the same base Cal. 600 architecture and A.260 size code as Cal. 635 above it, distinguished by function rather than grading tier: 630 is sweep-seconds without shock protection, 635 is small-seconds with shock protection, 645 is sweep-seconds with shock protection. Powers the semi-Bubbleback Oyster Perpetual 6084, 6085, and 6284, roughly 1948-1953. Jewel counts vary 17-20 across auction listings for the same caliber, consistent with market-specific tariff variants documented elsewhere in this family.
Cal. 740
| detail | value |
|---|---|
| type | Automatic |
| jewels | 18 |
| frequency | 18,000 vph (2.5 Hz) |
| size | 29.5mm |
The caliber behind the original Datejust: introduced 1945 with reference 4467, carrying Rolex's first automatic date mechanism in a wristwatch. Base architecture 720/730, size code A.295 — the slightly earlier sibling of the A.296 group above.
Cal. 745
| detail | value |
|---|---|
| type | Automatic |
| jewels | 18 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
| size | 29.5mm |
A calendar-equipped update to Cal. 740, documented on reference 6039, sharing a balance-staff and stem parts group with the whole 700/710/720/730/740/760/765/775 family.
Oyster and Oysterdate Precision
Precision is Rolex's non-chronometer manual line, a 10½-ligne family built alongside the automatic Bubbleback generation rather than after it, and the line that closed out Rolex's manual-wind era entirely — the Oysterdate Precision 6694 is documented as the last manual-wind Rolex ever put into production, outlasting even the hand-wound Daytona by a year. Six commercial numbers cover the family, distinguished by seconds placement, date, and beat rate rather than separate architectures.
Cal. 1210
| detail | value |
|---|---|
| type | Manual |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | ~58h |
| size | 4.27mm height |
The base caliber of the family: center (sweep) seconds, Breguet hairspring. Powers the Oyster Precision 6426 and an early Crott-catalogued example in ref. 6082. Fratello and Horbiter disagree on whether Cal. 1200 or Cal. 1210 is the true architectural base of the group; the point is unresolved between them.
Cal. 1215
| detail | value |
|---|---|
| type | Manual |
| frequency | 18,000 vph (2.5 Hz) |
| size | 5.07mm height |
Cal. 1210 with a date module added, the extra mechanism accounting for the jump from 4.27mm to 5.07mm in height. Powers the Oysterdate Precision 6694 in its early production and the earlier 6094/6294/6494 Oysterdate references. Non-quickset — the date advances only by running the hands through midnight.
Cal. 1216
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
A 17-jewel variant of Cal. 1215, otherwise architecturally identical.
Cal. 1220
| detail | value |
|---|---|
| type | Manual |
| frequency | 21,600 vph (one source gives 19,800 — see note) |
The Cal. 1210 platform without the Breguet overcoil, run at a raised beat rate. Horbiter, Fratello, and Chrono24 all give 21,600 vph; one specialist catalogue gives 19,800 vph for the same caliber, an unresolved discrepancy. Powers later-production Oyster Precision 6426.
Cal. 1225
| detail | value |
|---|---|
| type | Manual |
| power reserve | ~58h |
| size | 4.27 → 5.07mm height |
| shock | KIF |
Cal. 1220 with a date module added, carrying later-production Oysterdate Precision 6694 through the family's final years. None of the six Precision calibers on this page were chronometer-certified, which is why "Precision" rather than "Superlative Chronometer" appears on the dial across the whole line.
Cal. 1200
| detail | value |
|---|---|
| type | Manual |
| size | 3.65mm height |
The small-seconds variant of the family, thinner than the sweep-seconds Cal. 1210 it's otherwise architecturally close to.
Vintage sport calibers (Submariner, GMT-Master, Explorer, Air-King)
The sport time-only and GMT line runs through three broad chapters: the A-series and Cal. 1030 opening generation above, a long 15xx-family middle chapter, and the GMT branch's own parallel thread through the bakelite-bezel era. The 15xx family anchors Rolex's longest-running production stretch — Cal. 1530 through the early 1960s, Cal. 1520 as its permanent non-chronometer twin, and Cal. 1560/1570 carrying the chronometer side of Submariner, GMT-Master, and Explorer production into the 1980s.
Cal. 1030
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
| size | 28.5mm × 5.85mm |
Rolex's first bidirectional automatic, 1950–62, 25 jewels, 18,000 vph, 42 hours, 28.5 × 5.85mm: the caliber that ends the domed-caseback era. Its "butterfly" rotor, named for its cutaway wing-like shape, is stamped ROLEX PERPETUAL PATENTED and is the single most recognizable identifier for the caliber. Perlage finishing on the rhodium-plated mainplate, brushed (not striped) bridges, polished screw heads, and red anodized-aluminum reversing wheels round out the finishing. Regulation runs on a traditional pinned index rather than free-sprung Microstella, so a visible regulator arm near the balance is the fastest way to tell a 1030 apart from its free-sprung 1560/1570 successors at a glance. It first appears on the 6098 in 1952, running through the 6536, 6536-1, and 6538 Submariners, the 6610 Explorer, and the 6552 Air-King, in both COSC and non-COSC form on the identical movement. It was Rolex's first fully in-house automatic, no external ébauche supplier, with a 5.85mm profile thin enough to leave the bubble-caseback era behind for good.
Cal. 1035
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
| size | 28.5mm × 6.66mm |
The date version of Cal. 1030, from 1957, powering the Oyster Perpetual Date 6518, 6530, and 6534 and the Datejust Thunderbird 6609. Non-quickset — Rolex's own service documentation describes its calendar mechanism as "progressive," meaning the date creeps forward gradually through the night rather than jumping instantaneously at midnight, deliberately contrasted against the 1036 GMT caliber's instant-change wording in the same table.
Cal. 1530
| detail | value |
|---|---|
| type | Automatic |
| jewels | 17→25→26 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 44h |
1957–65, 17 jewels early rising to 25 then 26 late, 18,000 vph, 44 hours. Traditional Swiss lever escapement with a 15-tooth club-tooth wheel, screwed Glucydur balance. The rotor shape evolves mid-production from butterfly to half-moon, and later runs add blued screws on the auto-winding bridge with red Teflon-coated gears replacing brass — both genuine dating markers for a given example. First Submariner appearance is the 5510 in 1958–59, not yet chronometer-rated; chronometer certification arrives with Cal. 1560 on the 5512 instead. It also powers the 36mm Explorer-case 5504 Air-King alongside the early 5500 production, and Bonhams has catalogued it in a 1002 and a 1003 against the Watch-Wiki concordance that assigns it to the 5500 family only — a documented outlier, not a confirmed cross-reference pattern. Cal. 1530 was deliberately never COSC-certified across most of its run: regulating a labor-intensive screwed balance to chronometer tolerance at Rolex's production volume was judged uneconomical, a cost decision rather than a technical shortfall.
Cal. 1520
| detail | value |
|---|---|
| type | Automatic |
| jewels | 17 / 25 / 26 |
| frequency | 19,800 vph (2.8 Hz) |
The permanent non-chronometer twin of Cal. 1530, 1963–90, 17/25/26 jewels at 19,800 vph — the 17-jewel variant is a US/Canada import-duty-bracket move, not a different movement. Monometallic balance, index regulator, and a flat (non-Breguet) hairspring — the cost reduction that keeps it out of chronometer certification, confirmed across seven independent Antiquorum lot descriptions against occasional secondary sources that wrongly credit it with a Breguet overcoil. It powers late 5513, 5514, and 5517 Submariners and the long-running 5500 Air-King from 1963 onward, plus the 1002 Oyster Perpetual, 5501, and 5520.
Cal. 1535
| detail | value |
|---|---|
| type | Automatic |
| jewels | 26 |
| frequency | 18,000 vph (2.5 Hz) |
A date-module variant of Cal. 1530, from 1957, non-chronometer, powering the 5700/5701 Air-King-Date. This page previously had the 1525/1535 lineage reversed; Rolex's own factory caliber table (via Mark Sirianni's transcription) places 1535 as the earlier, 1530-based date module and 1525 as the later, 1520-based one below — a reading also required by the dates themselves, since a movement derived from Cal. 1520 can't predate 1520's own 1963 introduction. Currently single-sourced to that factory table; unpublished Rolex technical-manual PDFs referencing this caliber directly would settle it more firmly.
Cal. 1525
| detail | value |
|---|---|
| type | Automatic |
| jewels | 17 / 25 |
| frequency | 19,800 vph (2.8 Hz) |
A date-module variant of Cal. 1520, from 1965, non-chronometer, carrying the 5700/5701 Air-King-Date through its later production years — the higher-beat 19,800 vph sibling of Cal. 1535 above. The chronometer-rated date option in this generation runs on a related 1500-series caliber instead, in the 1500/1501/1503/1505 Oyster Perpetual Date.
Cal. 1560
| detail | value |
|---|---|
| type | Automatic |
| jewels | 26 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
1959–65, 26 jewels, 18,000 vph, 42 hours, the cross-family chronometer bridging Cal. 1530 and Cal. 1570 architecturally. It gains jewels over the 1530 and, like the 1570 after it, carries COSC certification, without yet reaching the 1570's higher 19,800 vph beat rate. The balance assembly is Rolex part number 7980: Microstella regulation screws, a free-sprung Breguet overcoil hairspring, and KIF Flector shock protection, the same balance package the 1570 inherits unchanged. Powers mid-production 5512, 1675, and 1016.
Cal. 1565
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
1959–65, 25 jewels, 18,000 vph, 42 hours, the "caller" GMT caliber in the early 1675 — 24-hour hand still linked to the main hour hand rather than jumping independently, the layout the whole GMT branch carries until Cal. 3085 breaks the pattern decades later.
Cal. 1570
| detail | value |
|---|---|
| type | Automatic |
| jewels | 26 |
| frequency | 19,800 vph (2.8 Hz) |
| power reserve | 44h |
| size | 28.5mm × 5.75mm |
1965–80, 26 jewels, 19,800 vph, 44 hours, 28.5 × 5.75mm — the higher-beat successor to Cal. 1560, with hacking added mid-life. Free-sprung Breguet hairspring with screw-based poising, two Microstella screws for regulation, Kif Ultraflex shock protection. It runs across the Submariner and Explorer lines through the late 1970s, and dealer listings that describe a "1500" as carrying Cal. 1575 are often describing a 1570 instead — the movement resolves the confusion, not the dial text.
Cal. 1575
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 19,800 vph (2.8 Hz) |
| power reserve | 50h |
1965–80, 25 jewels, 19,800 vph, 50 hours — adds either a date module or a GMT module onto the 1570 base, which is how the same caliber number lands on the 1680 (date), the late 1675 (GMT), and the 1655 Explorer II (GMT with 24-hour bezel) simultaneously.
GMT-Master line
The GMT branch reads in three distinct steps rather than a single continuous upgrade path. Cal. 1036 and 1065 belong to the bakelite-bezel 6542 era and keep the 24-hour hand synchronized to the main hour hand. Cal. 1565, 1575, and 3075 carry that same synchronized "caller" layout through the 1675 and 16750 generation. Cal. 3085 then breaks the pattern with the GMT branch's first independently jumping local hour hand, and Cal. 3175 keeps the older synchronized layout alive in parallel on the 16700 until 1999 even as Cal. 3185 and 3186 define the long 16710 run that follows.
Cal. 1036
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
1954–59, 25 jewels, 18,000 vph, 42 hours — the first GMT caliber, in the bakelite-bezel 6542. Rotor and bridge spell out "TWENTY FIVE JEWELS" in full rather than abbreviating it, an early-production engraving convention that helps date a given example.
Cal. 1065
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
1956–59, 25 jewels, 18,000 vph, 42 hours, the mid-6542 GMT caliber succeeding Cal. 1036 within the same bakelite-bezel generation.
Cal. 1066
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
1957–59, 25 jewels, 18,000 vph, 42 hours — the third and final movement Rolex fitted to the 6542 across its five-year run, replacing Cal. 1065 for the last two years of production. All three 6542 calibers (1036, 1065, 1066) share the base 1030 architecture with a GMT module added; Rolex changed the caliber number with each running revision rather than keeping one number through the reference's life, which is why an early and a late 6542 can carry different movements despite looking identical from the dial side.
Cal. 3075
| detail | value |
|---|---|
| type | Automatic |
| jewels | 27 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
1979–88, 27 jewels, 28,800 vph, 48 hours, hacking, quickset, chronometer — carries the synchronized "caller" GMT layout into the 16750/16753/16758 generation.
Cal. 3085
| detail | value |
|---|---|
| type | Automatic |
| jewels | 27 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
| size | 28.5mm × 6.3–7.2mm (sources disagree) |
1983–89, 27 jewels, 28,800 vph, 48 hours, hacking, chronometer. The first Rolex caliber to dissociate the local-hour hand from the 24-hour hand: with the crown in its second (one-click-out) position, turning it jumps the local hour hand forward or backward in full one-hour steps — snapping cleanly to each hour rather than sweeping through the minutes — while the minute and seconds hands, and the 24-hour "home time" hand, stay completely undisturbed. A traveler resets local time without touching the hand tracking home. The cost is quickset date, which now advances only via the local-hour hand. The 6.3mm figure widely quoted for its case-driving thickness is contradicted by Rolex's own parts diagram, which gives 7.20mm — either way the movement's thickness drove the 16760 "Fat Lady" / "Sophia Loren" case proportions, and it ran exclusively in the 16760 GMT-Master II and the 16550 Explorer II.
Cal. 3130
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
1999–2018, 31 jewels, 28,800 vph, 48 hours, hacking, chronometer — the time-only successor to Cal. 3000, carrying the 14060M, 114060, 114270, and 114200 through the 2000s and 2010s. The upgrade over the 3000 is a full balance bridge in place of a partial one, a larger balance wheel, and a Breguet overcoil hairspring — architecturally it's a date-less Cal. 3135, sharing that caliber's finishing standard rather than being a modest refresh of the simplified 3000.
Cal. 3132
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
2010–c.2020, 31 jewels, 28,800 vph, 48 hours, hacking, chronometer — Cal. 3130 with a Parachrom hairspring and Paraflex shock system added, powering the 214270 Explorer.
Cal. 3175
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
1988–99, 31 jewels, 28,800 vph, 48 hours, hacking, quickset, chronometer, adjusted to 5 positions and temperature, Glucydur balance with Microstella, Breguet hairspring, Kif shock. The last "caller" GMT and the last fixed-GMT caliber Rolex built, running in a single reference, the 16700 — the 24-hour hand stays linked to local hour, and the second time zone reads off the bezel rather than an independent hand, keeping the older synchronized layout alive right up to 1999 even as the rest of the GMT line had already moved on to the jumping-hour Cal. 3185.
Cal. 3185
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
| size | 6.45mm |
1989–c.2007, 31 jewels, 28,800 vph, 48 hours, hacking, quickset, chronometer, KIF Elastor shock. Derived directly from the Cal. 3135 platform with an added 24-hour GMT hand mechanism, powering the 16710, 16713, 16718, and 16570. Both Microstella nuts are always adjusted identically as a pair, a documented service note to avoid poise imbalance. At 6.45mm it's noticeably slimmer than the 7.2mm Cal. 3085 it replaced, part of why the 16710 case reads thinner on the wrist than the earlier "Fat Lady" 16760.
Cal. 3186
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 50h |
2007–19, 31 jewels, 28,800 vph, 50 hours, hacking, quickset, chronometer — adds a Parachrom hairspring to the Cal. 3185 base, carrying late 16710 production into the ceramic-bezel GMT line, the 116710LN, 116710BLNR, and 116719BLRO.
Cal. 3187
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48–50h (sources disagree) |
| size | 30.97mm |
An enlarged Cal. 3186, widened to push the date window outward for the 42mm Explorer II case — the same engineering trick Rolex used two years earlier on Cal. 3136 for the Datejust II. It powers the Explorer II 216570 exclusively, the first movement developed specifically for the Explorer line, running 2011 to 2021 before the 226570 and Cal. 3285 replaced it. Parachrom hairspring, Paraflex shock absorbers, and Breguet overcoil carry over from the 3185/3186 GMT lineage, paired with an independently-adjustable 24-hour GMT hand and a Superlative Chronometer −2/+2 rating.
Modern sport calibers (1988–2020)
The modern time-only line settles on the 31xx family, opening with Cal. 3000 as the first 28,800 vph no-date movement of the era and running through Cal. 3130 and 3132 in direct succession. Cal. 3135, the date-equipped counterpart introduced the same year as Cal. 3000, becomes the single dominant modern Rolex workhorse across three decades of Submariner Date production.
Cal. 3000
| detail | value |
|---|---|
| type | Automatic |
| jewels | 27 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 42h |
| size | 28.5mm × 5.8mm |
1989–99, 27 jewels, 28,800 vph, 42 hours (some owners report 45–60 hours in practice), 28.5 × 5.8mm — the first 28,800 vph time-only movement of the modern era, based on Cal. 3035 and powering the 14000 Air-King, 14010, 14060 Submariner, and 14270 Explorer. Deliberately simplified against the outgoing 1570 generation: a flat hairspring with no Breguet overcoil, and an adjustable-mass balance with no separate regulator arm at all. The automatic-winding module runs oversized components, including PTFE-coated red-alloy click wheels, and watchmakers commonly single out the winding module as the best-finished part of an otherwise deliberately economical movement.
Cal. 3035
| detail | value |
|---|---|
| type | Automatic |
| jewels | 27 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
1977–88, 27 jewels, 28,800 vph, 48 hours, hacking, quickset, chronometer — the first quickset Submariner caliber, in the 16800, 168000, 16808, and 16803. Quickset works by giving the crown an intermediate position that connects directly to the date wheel, bypassing the hour wheel entirely — on a non-quickset movement the only way to advance the date is to run the hands forward through midnight, sometimes dozens of times to skip a long month. The date wheel gear path runs differently through the movement than on a non-quickset caliber, which is why the feature can't be retrofitted after the fact.
Cal. 3135
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
1988–2018, 31 jewels, 28,800 vph, 48 hours, hacking, quickset, chronometer — Rolex's 30-year workhorse, running the 16610, 16613, and 16618 through to the 116610 generation. Rhodium-plated finish, beveled and polished chamfered screws, a two-piece axle-style bidirectional rotor, and four Microstella nuts for regulation that need a dedicated Microstella key. The reversing wheels (Rolex part 32135-540) are anodized purple-red and visible straight through the rotor cutout — an easy, no-disassembly identification marker. The hairspring material switched from Nivarox to Parachrom Blue circa 2007–2008, a running production change collectors use to help date an individual movement without opening the case.
Milgauss
Milgauss is Rolex's anti-magnetic line, and its two documented calibers sit half a century apart on two different base architectures — one built on the 1530-derived sport platform, the other on the modern date-less 3130 — evidence the anti-magnetic engineering gets bolted onto whatever mainstream movement is current rather than kept as its own standalone design lineage.
Cal. 1580
| detail | value |
|---|---|
| type | Automatic |
| jewels | 26 |
| frequency | 19,800 vph (2.8 Hz) |
| power reserve | 48h |
| size | 28.5mm × 5.75mm |
Powers the Milgauss 1019 exclusively across its entire 1960–1988 run, one of the longest single-caliber, single-reference pairings in Rolex's catalogue. It shares the 1530-derived platform with Cal. 1570 and 1575, with hacking added mid-production around 1972. The anti-magnetic engineering lives in the case rather than the movement: a soft-iron inner shield forms a Faraday cage around the caliber, which is why the 1019's case runs thicker than its Submariner and GMT-Master contemporaries built on the same movement family. Parts interchange broadly across the whole 1520/1525/1530/1535/1555/1556/1560/1565/1570/1575/1580 group.
Cal. 3131
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
| size | 28.5mm |
| shock | KIF |
A date-less Cal. 3130 derivative built for the Milgauss 116400 and 116400GV "Glace Verte" (2007–2023), and the Air-King 40 ref. 116900 (2016–2022). Anti-magnetism runs three layers deep rather than one: a two-part soft-iron shield around the movement — its interior engraved with a "B" and arrow, the symbol for magnetic flux density, visible only to Rolex-trained watchmakers — a paramagnetic blue Parachrom hairspring, and an escape wheel and pallet fork machined in amorphous nickel-phosphorus rather than steel, the detail most write-ups skip. COSC-certified for its entire run, the 3131 never received the Chronergy escapement or the tightened −2/+2 Superlative rating that later reached the rest of the sport line — the Milgauss was discontinued before that upgrade cycle arrived.
Daytona chronograph (manual-wind)
The manual-wind Daytona stays on Valjoux 72 architecture for its entire first chapter, 1963 through 1988, moving through five caliber numbers as Rolex progressively finished and then re-rated the same base ébauche. Valjoux was an independent Swiss ébauche manufacturer — it built the unfinished movement blank, not a complete Rolex-designed caliber — absorbed into the Ebauches SA holding group in 1944 and folded more fully into what became ETA in 1965, though movements kept the Valjoux name through the end of 72 production in 1974. Rolex was Valjoux's biggest single customer for this caliber: research into surviving case numbers puts at least 62,000 Valjoux 72/23 movements inside Rolex cases across more than 40 references, something like 7% of total Valjoux 72 output, Rolex's demand alone likely helped keep the column-wheel chronograph in production as long as it stayed viable. Heuer, Universal Genève, Longines and others built chronographs on the same base; what distinguished a Rolex example was the finishing and rate adjustment applied after the ébauche left Valjoux, not a different movement underneath.
Cal. 72
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 48h |
1960–65, 17 jewels, 18,000 vph, 48 hours — a bare Valjoux 72 with minimal Rolex finishing, in the 6234 and earliest 6238.
Cal. 72A
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 48h |
Early-to-mid 1960s, 17 jewels, 18,000 vph, 48 hours — a Rolex-finished intermediate step between Cal. 72 and 72B; thinly documented in the collector record.
Cal. 72B
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 48h |
1962–65, 17 jewels, 18,000 vph, 48 hours: the final pre-722 Valjoux 72 execution, in the early 6238. Watch historian Pucci Papaleo, who has serviced large numbers of these movements, states there is no substantial mechanical difference between the 72B and the 722 that follows it. The name change reflects Rolex re-branding the same finished movement for its own advertising and parts catalogues, not a new architecture.
Cal. 722
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 48h |
1963–69, 17 jewels, 18,000 vph, 48 hours — the first Rolex-stamped Valjoux 72, powering the original 6239 alongside the 6240 and 6241 generation, the run that includes the "Paul Newman" dial variants.
Cal. 722-1
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 48h |
1969–70, 17 jewels, 18,000 vph, 48 hours — a transitional revision of Cal. 722 bridging into the higher-beat Cal. 727 era. Unlike the largely cosmetic 72B-to-722 rename, this one is a genuine mechanical change: Rolex altered the shape of the hour-recorder conveyor in the chronograph coupling mechanism so it engaged more smoothly with its driving wheel, the fix that let the higher-beat 727 run reliably at 21,600 vph shortly after.
Cal. 727
| detail | value |
|---|---|
| type | Manual |
| jewels | 17 |
| frequency | 21,600 vph (3 Hz) |
| power reserve | 48h |
1970–88, 17 jewels, 21,600 vph, 48 hours: the higher-beat Valjoux 72 that lifts the rate from 18,000 to 21,600 vph and runs through the 6262, 6263, 6264, and 6265 until the manual-wind Daytona era closes in 1988. The photographed comparison is a specialist side-by-side of two period movements, one catalogued as a "Rolex Daytona Ref. 6263" in quotation marks, the other a confirmed genuine 6265 with "727" plainly engraved. It doubles as a useful authentication reference: matching a movement's engraved caliber number against what a listing claims separates a documented example from a franken watch.
Daytona chronograph (automatic)
Cal. 4030
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 52–54h (sources disagree) |
1988–2000, 31 jewels, 28,800 vph, 54 hours, chronometer — Rolex's most disputed movement specification, and the last foreign-sourced caliber in its modern line. The working outline is a heavily reworked Zenith El Primero base, launched with the 16520 for a twelve-year run; serious sources agree on the 28,800 vph rate, a free-sprung Breguet balance, and no date function, but diverge on the exact length of Rolex's modification list and quote the power reserve as either 52 or 54 hours depending on source. The photographed example, marked "MONTRES ROLEX S.A. GENEVA SWISS, ADJ. 5 POSITIONS TEMPERATURE, THIRTY-ONE JEWELS" with "4030" in a small stamped box, is a clean confirmation of the caliber regardless of which modification-list version a given source favors.
Cal. 4130
| detail | value |
|---|---|
| type | Automatic |
| jewels | 44 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 72h |
2000–present, 44 jewels, 28,800 vph, 72 hours, chronometer: Rolex's first fully in-house chronograph movement, launched with the 116520. Column-wheel construction with a vertical clutch, 201 components, and the first Rolex chronograph to run on a ceramic ball-bearing rotor (7 balls on 3 screws) rather than a sleeve bearing, cutting the part count below the Cal. 4030 it replaced despite the added complexity. Solid caseback only; the display back doesn't arrive until the 4131 successor in 2023. The vented rotor carries a proprietary Rolex striping pattern, a visual tell against generic aftermarket rotors sometimes swapped into grey-market builds. It powered the whole pre-ceramic in-house Daytona generation and carried forward into the 116500LN.
Day-Date
The Day-Date runs on its own caliber family, entirely separate from the sport and Oyster Perpetual movements documented above. Quickset arrives only with the 5-digit generation — every 4-digit Day-Date sets the day and date exclusively by running the hands through midnight.
Cal. 1055
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
1956–1959, 25 jewels, 18,000 vph, 42 hours — Rolex's first day-and-date caliber, carried by the originals-era 6510, 6511, 6611, 6612, and 6613. Straight-line Swiss lever escapement, KIF shock protection, monometallic balance adjusted to temperature and five positions, self-compensating Breguet balance spring. Rhodium-plated, with oeil-de-perdrix ("partridge-eye") circular graining on the finish rather than Côtes de Genève stripes. The generation-1 movement (6510/6511) pre-dates COSC certification; the generation-2, engraved "1055B" on the bridge rather than "1055," adds full COSC rating and carries "Superlative Chronometer Officially Certified" on the dial in place of the earlier "Officially Certified Chronometer" script. Sources disagree on whether the free-sprung Microstella balance is a 1055B-only upgrade or already present on the base 1055 — both readings appear in the record, unresolved. No quickset, no hacking, on either generation.
Cal. 1555
| detail | value |
|---|---|
| type | Automatic |
| jewels | 25 |
| frequency | 18,000 vph (2.5 Hz) |
| power reserve | 42h |
| size | 7.03mm |
1959–c.1965, 25 jewels, 18,000 vph, 42 hours, chronometer, still non-quickset and non-hacking — a Cal. 1055-derived movement carrying the early 4-digit Day-Date (1803, 1804, 1806, 1807, 1811). Free-sprung beryllium-bronze balance with four gold-toned Microstella regulation nuts visible on the balance rim, the clearest visual break from the pinned-regulator 1030/1530 generation running in parallel on the sport watches. Height grew to 7.03mm to house the day-disc mechanism, and early production (1959 to c.1970) pairs with the stepped "pie-pan" dial profile collectors track as a separate variant.
Cal. 1556
| detail | value |
|---|---|
| type | Automatic |
| jewels | 26 |
| frequency | 19,800 vph (2.8 Hz) |
| power reserve | 42h |
c.1965–1977/78, 26 jewels, 19,800 vph, 42 hours, chronometer, still no quickset — a higher-frequency successor to Cal. 1555, carrying the mid-and-late 4-digit Day-Date (1803, 1804, 1806, 1807, 1811). Hacking was added mid-production in 1972; examples built before that date do not hack, a genuine running change rather than a running fault.
Cal. 1566
| detail | value |
|---|---|
| type | Automatic |
| jewels | 26 |
| escapement | Straight-line lever |
| balance | Monometallic, free-sprung Breguet spring |
The only caliber Rolex built for a single specific case: the platinum Day-Date 1831, commissioned for the Shah of Iran and delivered from 1977, the heaviest production Rolex ever made at 290 grams. Antiquorum's 2013 sale of example No. 05 (case 5'086'932, CHF 206,500) catalogues the movement directly: rhodium-plated, 26 jewels, straight-line lever escapement, monometallic balance adjusted to temperature and five positions, free-sprung Breguet balance spring, Microstella regulating screws, hacking. Sources disagree on how many 1831s exist — the lot's own catalogue title says eight, other researchers say nine — and on the movement itself: one concordance assigns the reference to Cal. 1556 instead of 1566, against the auction houses that physically examined the watches. Both figures are worth keeping in view rather than resolved.
Cal. 3055
| detail | value |
|---|---|
| type | Automatic |
| jewels | 27 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
1977–1988, 27 jewels, 28,800 vph, 48 hours, hacking, chronometer — the first Day-Date caliber with any quickset at all, though only for the date; the day still advances by running the hands. Sapphire-crystal era, carrying the 18038, 18048, 18078, and early 18238. The day-disc mechanism sits visibly on the dial-side plate, distinct from the rotor-side bridge finishing shown on the earlier 1055/1555/1556 generation.
Cal. 3155
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
1988–2019, 31 jewels, 28,800 vph, 48 hours, hacking, chronometer: adds the day quickset that Cal. 3055 lacked. Pull the crown to its first position and the same motion sets both functions in opposite directions: turn clockwise to advance the date, counterclockwise to advance the day. Cal. 3055 could only do half of that. The double-quickset the 18238 introduced carried the 6-digit 118238 family for three decades on the same movement.
Cal. 3156
| detail | value |
|---|---|
| type | Automatic |
| jewels | 31 |
| frequency | 28,800 vph (4 Hz) |
| power reserve | 48h |
| size | 30.97mm |
2008–2015, 31 jewels, 28,800 vph, 48 hours, hacking, double quickset, chronometer — a Cal. 3155 derivative built for the 41mm Day-Date II, with a Parachrom hairspring and Paraflex shock added, powering the 218238, 218239, 218206, and 218235. It shares its 30.97mm main plate — 2.5mm wider than the standard 28.5mm Rolex automatic, to carry an enlarged day/date wheel — with three other oversized calibers: 3132, 3136, and 3187, all built to push the date window outward in an enlarged case. Most published specs list this caliber at the standard 28.5mm, an error worth correcting on sight.
Oysterquartz
The Oysterquartz sits outside the mechanical line entirely: Rolex's own in-house quartz calibers, launched in 1977 and run through 2001, with total output staying small — under about 25,000 watches across the full 24-year production span. Their origin traces to a genuine industry crisis: by the late 1960s Japanese quartz technology, Seiko's above all, threatened to make Swiss mechanical watchmaking obsolete almost overnight, and Rolex joined a consortium of Swiss manufacturers called the Centre Electronique Horloger (CEH) to develop a shared response. That collaboration produced the Beta 21, which powered Rolex's first quartz watch, the 1970 reference 5100 — a movement Rolex never fully embraced, since the Beta 21 architecture wouldn't fit a proper Oyster case and the 5100 shipped merely water-resistant rather than waterproof. Rolex left the CEH consortium in 1972 and spent five years developing its own quartz architecture in-house, releasing the results as cal. 5035 and 5055 in 1977, built from scratch rather than a rebadged Beta 21.
Cal. 5035
| detail | value |
|---|---|
| type | Quartz |
| jewels | 11 |
| frequency | 32,768 Hz crystal |
1977–2001, 11 jewels, hacking, quickset, chronometer, running on a single 32,768 Hz quartz crystal and a 1.55V cell — powers the Oysterquartz Datejust and Oyster Perpetual references, including the 17000, 17013, and 17014. Despite the popular "stepper motor" description, the mechanism is a true anchor escapement in miniature: a pulse motor drives a pallet fork, which drives a pallet wheel carrying the seconds hand directly at one tick per second, with the hour and minute hands geared off that same wheel — the fork locks the wheel between pulses, giving zero backlash, and the audible tick is the pallet engaging the wheel rather than a stepper advancing. Rate is thermocompensated by the forced-constant-frequency (TCVCXO) method and is user-adjustable at service via a trimmer condenser, which lets a watchmaker correct for the small frequency drift quartz crystals accumulate with age. Rolex never published an official accuracy figure; documented estimates range from under a minute to under a second a year depending on the source, a spread wide enough that none of them should be taken as authoritative.
Cal. 5055
| detail | value |
|---|---|
| type | Quartz |
| jewels | 11 |
| frequency | 32,768 Hz crystal |
1977–2001, 11 jewels, hacking, quickset, chronometer — the Day-Date counterpart to Cal. 5035, powering the Oysterquartz Day-Date 19018 in yellow gold and 19019 in white gold, plus the pyramid-bezel 19028.
Related but not Rolex
Two commonly-confused calibers turn up in Prince and Bubbleback research but aren't Rolex movements at all. Gruen's Cal. 877, used in the Techni-Quadron, is the Aegler architectural sibling of Cal. 300 sold under Gruen's own brand for the US market — the shared supplier explains the identical layout, but it was never a Rolex commercial number. And any Bubbleback-era "9¾ ligne" or "9¾ lignes" note on a reference page means only that the movement's size class was documented, not the specific caliber number — a real gap in the source, not a claim that a distinct "9¾ ligne caliber" exists as its own entry.
Sources
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- Hodinkee — A Vintage Watch Nerd's Critical Dissection of the Rolex Daytona, Part 1 (Paul Boutros, 2012)
- Hodinkee — A Vintage Watch Nerd's Critical Dissection of the Rolex Daytona, Part 2 (Paul Boutros, 2013)
- Monochrome — In-Depth: The History of the Rolex Daytona (Erik Slaven, 2024)
- Monochrome — History of the Rolex Submariner, Part 1 (Tom Mulraney, 2020)
- Monochrome — History of the Rolex Submariner, Part 2 (Tom Mulraney, 2020)
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- Monochrome — The History of the Rolex Explorer (Frank Geelen, 2024)
- Monochrome — In-Depth: The History of the Rolex Explorer II
- Monochrome — Youngtimer Case Study, the Rolex Explorer 14270 (Frank Geelen, 2020)
- Monochrome — Rolex Explorer 214270 In-Depth Review (Brice Goulard, 2016)
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- Revolution — The Rolex "John Player Special" Paul Newman Daytona Ref. 6241 (Bob Ridley, 2017)
- A Collected Man — Is the Rolex Pre-Daytona a Forgotten Classic? (Russell Sheldrake, 2020)
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- Sotheby's — Submariner Ref 6536/1, Stainless Steel Automatic With Bracelet, Circa 1957
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- Caliber Corner — per-caliber technical database
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- Antiquorum — auction lot catalogue
- Christie's — auction lot catalogue
- Sotheby's — auction lot catalogue
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- The Vintage Rolex Field Manual — Colin A. White, Morning Tundra