Reference:5517: Difference between revisions

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The 5517 is the MilSub: the British military Submariner, purpose-built for the Royal Navy and never sold through any retail channel. Production ran to roughly 1,200 units, and only around 180 are accounted for in collector databases. A 1978 example sold at Sotheby's in November 2023 for 482,600 CHF, the highest MilSub auction result on record, putting the 5517 alongside the earliest and rarest Submariners despite being a 1970s watch.

Core facts

detail	value
reference	5517
family	Submariner (no date, military-issue)
distribution	Royal Navy (British military), no retail
movement	caliber 1520 (disputed; forum collectors argue 1570)
case	40mm, fixed bars (soldered, non-removable spring bars)
crystal	acrylic
bezel	60-minute (full-minute markings around entire bezel)
dial	T SWISS T designation (tritium)
caseback	broad arrow, circled T, military service number
hands	Mercedes (early batches), broadsword/plongeur (Batch 3)
total production	approximately 1,200 units
accounted for	roughly 180 examples

Where it sits in the line

The 5517 sits outside the ordinary retail no-date Submariner line. The 5513 was used by various military forces, but those were standard commercial watches procured through military channels. The 5517 was built for British military diving with specifications that appear on no retail Submariner: fixed bars soldered into the lugs, a 60-minute bezel graduated all the way around, a T SWISS T tritium dial, and military caseback markings. Each was a Ministry of Defence requirement rather than a Rolex commercial choice.

The 5514 (COMEX) and the 5517 are the two non-retail branches of the 5513 era, and they sit in different worlds. The 5514 was a civilian-professional watch issued to a French commercial diving company. The 5517 was military, issued to the Royal Navy.

Production outline

Production ran in three batches, each with its own caseback and hand signature. Total output was roughly 1,200 units, of which about 180 are accounted for in collector databases and auction records. The remainder are lost, destroyed through military use, or sitting undiscovered. The scarcity is a structural part of how the watch trades.

Batch 1: 5513 case engravings between 12 lugs

The first batch still carries 5513 lug engravings, the clearest sign that the 5517 starts as a military adaptation of the commercial case rather than a separate case family.

Serial bands fall between roughly 3M and 4M, putting the run in the early 1970s — about 1971 to 1974. The lower boundary is not fixed from factory records.

Batch 2: 5513 engravings plus 5517 stamp under 7 lug

The second batch keeps the 5513 engravings between the twelve lugs and adds a 5517 reference stamp under the seven lug. Some examples carry both styles on the same caseback at the same time, the dual-marking pattern that captures the transition from repurposed 5513 cases to dedicated 5517 production. The Sotheby's December 2019 lot, sold as a 5513/5517 c.1974, fits this transitional character.

Serial bands run between roughly 4M and 5M, mid-1970s production, about 1975 to 1977.

Batch 3: 5517 engravings between lugs with broadsword hands

The third and final batch carries 5517 engravings between the lugs and the broadsword hands that most collectors now picture when they say MilSub. This is the late, full-spec form of the reference.

Serial bands run between roughly 5M and 6M, late-1970s production, about 1977 to 1980.

All three serial bands are collector approximations cross-referenced from auction records, private sales, and reference catalogues rather than factory data. The Royal Navy never published procurement lists by serial number, and Rolex does not confirm military issue dates. The ranges are internally consistent across auction catalogues and represent the current collector consensus, not factory boundaries.

Movement notes

The 5517 movement is disputed. Published source work leans toward caliber 1520. Forum collectors argue for caliber 1570. Both readings stay alive until direct movement evidence surfaces.

Dial map

T SWISS T designation

The 5517 dial carries the T SWISS T designation, with the letter T flanking SWISS at the bottom of the dial. Both T markers signal a tritium radiation source, the isotope used for watch luminescence in this era. The dual-T format was legally required under UK regulations for tritium-lumed watches. It is one of the cleanest single-glance separators between a MilSub dial and a commercial 5513 dial.

Standard military dial

The dial carries the SUBMARINER model text and, on most examples, Rolex Oyster Perpetual above centre. Most MilSub dials carry no depth rating, in metric or imperial; the Ministry of Defence did not call for one. Military identity is carried by the T SWISS T marking, the caseback engravings, and the case modifications, not by a separate dial design.

Maxi I dial

The Sotheby's 2023 lot is described as a Maxi I dial. Maxi follows the same logic as on the late 5513: enlarged lume plots for legibility, in the last years of matte-dial production. The 1978 production date lines up with Maxi I placement on the 5513 timeline.

Broadsword hand variants

Third-batch examples carry broadsword (plongeur) hands, wider and more sword-shaped than the standard Mercedes hand and absent from every retail Submariner. On a wrist or in a photograph, they are the fastest visual cue that the watch is a MilSub.

Case, bezel, crystal, and crown

Fixed bars

Fixed bars are the key structural identifier. Strap bars are soldered permanently into the lugs rather than fitted as removable spring bars, so the strap cannot detach underwater if a bar fails. They are sized for NATO-style fabric pass-through and will not take a standard Oyster bracelet.

60-minute bezel

The 60-minute bezel carries minute gradations all the way around rather than only at five-minute intervals, giving the diver minute-by-minute elapsed-time tracking for decompression. It was a Ministry of Defence requirement and appears on no retail Submariner of the period.

Case engravings and caseback markings

Military-issue watches carry specific engravings on the caseback and between the lugs, varying by batch as set out above. Correct, matching military markings are the primary authentication test for any 5517.

The dual-engraving pattern splits cleanly between maker and customer. Rolex reference and production markings sit on the inner caseback. Military identification (broad arrow, circled T, NATO stock numbers, service numbers) sits on the outer caseback. The inside/outside split holds across all three batches and is the first place a serious buyer looks.

The broad arrow is the British government property mark, stamped into the outer caseback and present on most 5517 examples. Any broad-arrow watch in the civilian market either left service through official decommissioning or carries an unclear chain of custody. The mark itself is never a civilian or retail marking.

The circled T is the UK legal requirement under the Radioactive Substances Act for tritium-containing items. It typically appears next to the broad arrow, marking military ownership and regulatory compliance in the same engraving block.

Many examples carry a NATO stock number beginning 0552, the Ministry of Defence procurement prefix, and a correctly formatted 0552 number is consistent with authentic MOD procurement. An individual service number or unit identifier is often engraved alongside, linking the watch to a specific sailor or diving unit. Cross-referencing a service number against Royal Navy records, where accessible, is the most rigorous provenance check available for the reference.

Bracelets, end links, clasps, and packaging notes

Military-issue watches were delivered on NATO-style fabric straps rather than metal bracelets, in keeping with the fixed-bar design. The bars do not take a standard Oyster bracelet, and the NATO pass-through is deliberate: the strap continues beneath the watch even if one bar fails, so the watch stays on the wrist. Packaging followed procurement logistics. Watches arrived in military stores packaging, not standard Rolex retail boxes.

Special branches

Batch 3 broadsword

Third-batch broadsword examples are the most collected and most valuable form of the reference. Dedicated 5517 engravings, broadsword hands, fixed bars, and the 60-minute bezel are the full-specification MilSub in one watch.

Batch 1 transitional

First-batch examples with 5513 engravings show the 5517 before it developed its own caseback identity. They are the earliest military-specific Submariners in the 5517 programme.

Authentication warning

The 5517 is one of the most faked Rolex references in the market. Extreme value (consistently above $200,000 at auction), a comparatively simple base watch (a modified 5513), and the difficulty of verifying military provenance combine to make the reference a fraud target.

The conversion path is short: a standard 5513 takes fixed bars, a 60-minute bezel, military caseback engravings, and broadsword hands. Each step is within reach of a skilled watchmaker, and the finished result can be visually convincing to anyone who has not handled a genuine example.

Three checks carry most of the authentication weight. First, documented provenance: a chain of custody connecting the watch to a specific Royal Navy unit or service number, verifiable against military records where those records are accessible. Second, physical inspection by a specialist who can read fixed-bar construction, caseback engraving depth and consistency, bezel graduation quality, and hand proportions against genuine military specification. Third, cross-reference against known examples; with only about 180 accounted for, the specialist community is small enough that most genuine watches are tracked.

The fake problem is not theoretical. Specific fraudulent conversions have been documented at auction and through private dealers, and authentication should be treated as the load on any 5517 purchase.

Historical market and auction record

Three auction results frame the 5517 as a consistent six-figure reference across different examples.

Sotheby's, November 2023: a MilSub c.1978 sold for 482,600 CHF and reset the auction ceiling for the reference. That result is now the reference point for a full-spec late watch.

Sotheby's, November 2018: a 5517 c.1978 sold for 218,750 CHF, documented with caliber 1520, military issue numbering, and a Rolex presentation case, against an estimate of 150,000 to 300,000 CHF.

Sotheby's, December 2019: a 5513/5517 c.1974 sold for $262,500. The lot bridges the 5513 and 5517 designations, consistent with the Batch 1 and Batch 2 examples where 5513 and 5517 markings coexist on one caseback.

Three results above $200,000 in their respective currencies, inside a five-year window, for a watch produced in roughly 1,200 units with only 180 accounted for. The rarity is structural rather than statistical. It was made for one client, in limited procurement batches, to be used operationally, and most of these watches had hard lives.

The value drivers are also specific. A 5517 reaches prices above $250,000 because it carries genuine military provenance rather than retail stock, period-correct tritium lume aged naturally across five decades, and physical specification unavailable on any retail watch (fixed bars, 60-minute bezel, broadsword hands). Each factor adds value on its own; together they produce results that regularly clear pre-auction estimates.

The market runs on batch type, completeness of military documentation, and physical condition. Third-batch broadsword examples in full-spec condition, with documented provenance, the service number on the caseback, the matching inside number, and an original T SWISS T dial in an unpolished case, sit at the top of the MilSub market.

Sources

The Vintage Rolex Field Manual — Colin A. White, Morning Tundra
History of the Rolex Submariner - Part 2, The 55XX References and 1680 Date — Tom Mulraney, Monochrome
Inside Mike Wood's 'For Exhibition Only': A Private Rolex Collection On Limited Display — Tim Vaux, Hodinkee
Full Spec Military Submariner, Reference 5517, Circa 1978 — Sotheby's, Sotheby's
MilSub Submariner, Ref 5517, Stainless Steel Military Wristwatch Made for the British Armed Forces, Circa 1978 — Sotheby's, Sotheby's

@@ Line 12: / Line 12: @@
 }}
-<small>[[Reference:submariner|Submariner]] → '''5517'''</small>
+<small>[[Reference:submariner|Submariner]] -> '''5517'''</small>
-The 5517 is the MilSub — collector shorthand for the British military Submariner — purpose-built for the Royal Navy and never sold through any retail channel. Approximately 1,200 units were produced; only around 180 are accounted for in collector databases. When a 5517 surfaces at auction, it is an event. A 1978 example sold at Sotheby's in November 2023 for 482,600 CHF, the most expensive MilSub auction result on record. That puts the 5517 in the company of the earliest and rarest Submariners despite being a 1970s watch. Military provenance, purpose-built specification, and genuine scarcity do that to collector value.
+The 5517 is the MilSub: the British military Submariner, purpose-built for the Royal Navy and never sold through any retail channel. Production ran to roughly 1,200 units, and only around 180 are accounted for in collector databases. A 1978 example sold at Sotheby's in November 2023 for 482,600 CHF, the highest MilSub auction result on record, putting the 5517 alongside the earliest and rarest Submariners despite being a 1970s watch.
 <span id="core-facts"></span>
@@ Line 67: / Line 67: @@
 == Where it sits in the line ==
-The 5517 sits outside the ordinary retail no-date Submariner line. The 5513 was also used by various military forces, but those were standard commercial watches procured through military channels. The 5517 was purpose-built for British military diving use with specifications that do not appear on any retail Submariner. Fixed bars (spring bars soldered in place so they cannot be removed), a 60-minute bezel (minute gradations all the way around), a T SWISS T tritium dial, and military caseback markings are all features driven by Ministry of Defence requirements rather than Rolex commercial design.
+The 5517 sits outside the ordinary retail no-date Submariner line. The 5513 was used by various military forces, but those were standard commercial watches procured through military channels. The 5517 was built for British military diving with specifications that appear on no retail Submariner: fixed bars soldered into the lugs, a 60-minute bezel graduated all the way around, a T SWISS T tritium dial, and military caseback markings. Each was a Ministry of Defence requirement rather than a Rolex commercial choice.
-The 5514 (COMEX) and the 5517 (MilSub) are the two major non-retail branches of the 5513 era, and they are distinct. The 5514 is civilian-professional, issued to a French commercial diving company; the 5517 is military, issued to the Royal Navy.
+The 5514 (COMEX) and the 5517 are the two non-retail branches of the 5513 era, and they sit in different worlds. The 5514 was a civilian-professional watch issued to a French commercial diving company. The 5517 was military, issued to the Royal Navy.
 <span id="production-outline"></span>
 == Production outline ==
-The 5517 was produced in approximately three batches, each with distinct identifying features. Total production was roughly 1,200 units. Of those, approximately 180 have been accounted for in collector databases and auction records, meaning the majority of production is either lost, destroyed through military use, or sitting in undiscovered collections. That scarcity arithmetic is a core part of why the watch commands the prices it does.
+Production ran in three batches, each with its own caseback and hand signature. Total output was roughly 1,200 units, of which about 180 are accounted for in collector databases and auction records. The remainder are lost, destroyed through military use, or sitting undiscovered. The scarcity is a structural part of how the watch trades.
 <span id="batch-1-5513-case-engravings-between-12-lugs"></span>
 === Batch 1: 5513 case engravings between 12 lugs ===
-The first batch still shows its 5513 roots in the lug engraving format. That is one of the clearest reminders that the 5517 begins as a military adaptation of the commercial case rather than as an entirely separate case family.
+The first batch still carries 5513 lug engravings, the clearest sign that the 5517 starts as a military adaptation of the commercial case rather than a separate case family.
-Collector documentation places Batch 1 in the 3M–4M serial range, consistent with early-1970s Rolex production (approximately 1971–1974). The exact lower boundary is not established from factory records.
+Serial bands fall between roughly 3M and 4M, putting the run in the early 1970s — about 1971 to 1974. The lower boundary is not fixed from factory records.
 <span id="batch-2-5513-engravings-plus-5517-stamp-under-7-lug"></span>
 === Batch 2: 5513 engravings plus 5517 stamp under 7 lug ===
-The second batch retains the 5513-style engravings between the twelve-o'clock lugs but adds a 5517 reference stamp under the seven-o'clock lug. Some examples carry both engraving styles on the same caseback, the 5513 markings between the twelve lugs and the 5517 stamp below the seven lug simultaneously. That dual-marking pattern represents the transition from repurposed 5513 cases to dedicated 5517 production. The Sotheby's December 2019 lot, sold as a 5513/5517 c.1974, fits the Batch 2 transitional character.
+The second batch keeps the 5513 engravings between the twelve lugs and adds a 5517 reference stamp under the seven lug. Some examples carry both styles on the same caseback at the same time, the dual-marking pattern that captures the transition from repurposed 5513 cases to dedicated 5517 production. The Sotheby's December 2019 lot, sold as a 5513/5517 c.1974, fits this transitional character.
-Collector documentation places Batch 2 in the 4M–5M serial range, consistent with mid-1970s production (approximately 1975–1977).
+Serial bands run between roughly 4M and 5M, mid-1970s production, about 1975 to 1977.
 <span id="batch-3-5517-engravings-between-lugs-with-broadsword-hands"></span>
 === Batch 3: 5517 engravings between lugs with broadsword hands ===
-The third and final batch carries 5517 engravings between the lugs and the broadsword hands most collectors now picture when they think MilSub. That is the visually decisive late form of the reference.
+The third and final batch carries 5517 engravings between the lugs and the broadsword hands that most collectors now picture when they say MilSub. This is the late, full-spec form of the reference.
-Collector documentation places Batch 3 in the 5M–6M serial range, consistent with late-1970s production (approximately 1977–1980).
+Serial bands run between roughly 5M and 6M, late-1970s production, about 1977 to 1980.
-The serial bands above are collector-documented approximations derived from cross-referencing auction records, private sales, and reference catalogues rather than Rolex factory data. The Royal Navy never published procurement lists organized by serial number, and Rolex does not confirm military issue dates. The ranges are internally consistent across auction catalogues and represent the best current collector understanding, not exact factory-record boundaries.
+All three serial bands are collector approximations cross-referenced from auction records, private sales, and reference catalogues rather than factory data. The Royal Navy never published procurement lists by serial number, and Rolex does not confirm military issue dates. The ranges are internally consistent across auction catalogues and represent the current collector consensus, not factory boundaries.
 <span id="movement-notes"></span>
 == Movement notes ==
-The 5517 movement remains disputed. Published source work leans toward cal. 1520, while some forum collectors argue for 1570. Until more direct movement evidence surfaces, both readings stay alive.
+The 5517 movement is disputed. Published source work leans toward caliber 1520. Forum collectors argue for caliber 1570. Both readings stay alive until direct movement evidence surfaces.
 <span id="dial-map"></span>
@@ Line 110: / Line 110: @@
 === T SWISS T designation ===
-The 5517 dial carries the T SWISS T designation — the letter T before "SWISS" and again after it at the bottom of the dial. Both T markers indicate the dial contains a tritium radiation source, the radioactive isotope used for watch luminescence in this era. The dual-T designation was legally required under UK regulations for tritium-lumed watches. T SWISS T distinguishes the MilSub dial from commercial 5513 examples, which carry the standard country designation without the T markers.
+The 5517 dial carries the T SWISS T designation, with the letter T flanking SWISS at the bottom of the dial. Both T markers signal a tritium radiation source, the isotope used for watch luminescence in this era. The dual-T format was legally required under UK regulations for tritium-lumed watches. It is one of the cleanest single-glance separators between a MilSub dial and a commercial 5513 dial.
 <span id="standard-military-dial"></span>
 === Standard military dial ===
-The 5517 dial carries the "SUBMARINER" model text and, on most examples, "Rolex Oyster Perpetual" above center. Most MilSub dials do not carry a depth rating in metric or imperial. The Ministry of Defence did not specify depth-rating text as a dial requirement. The military identity is established by the T SWISS T marking, the caseback engravings, and the structural modifications to the case, rather than by a completely different dial design.
+The dial carries the SUBMARINER model text and, on most examples, Rolex Oyster Perpetual above centre. Most MilSub dials carry no depth rating, in metric or imperial; the Ministry of Defence did not call for one. Military identity is carried by the T SWISS T marking, the caseback engravings, and the case modifications, not by a separate dial design.
 <span id="maxi-i-dial"></span>
 === Maxi I dial ===
-The strongest direct lot in the package — Sotheby's 2023 — describes a Maxi I dial. Maxi here follows the same logic as the 5513 Maxi era: enlarged lume plots for improved legibility, late in matte-dial production. The 1978 production date is consistent with Maxi I placement on the 5513 timeline.
+The Sotheby's 2023 lot is described as a Maxi I dial. Maxi follows the same logic as on the late 5513: enlarged lume plots for legibility, in the last years of matte-dial production. The 1978 production date lines up with Maxi I placement on the 5513 timeline.
 <span id="broadsword-hand-variants"></span>
 === Broadsword hand variants ===
-Third-batch examples with broadsword hands are visually distinct from earlier batches. The broadsword (plongeur) hand is wider and more sword-shaped than the standard Mercedes hand and does not appear on any retail Submariner. This is the most immediately recognizable MilSub feature.
+Third-batch examples carry broadsword (plongeur) hands, wider and more sword-shaped than the standard Mercedes hand and absent from every retail Submariner. On a wrist or in a photograph, they are the fastest visual cue that the watch is a MilSub.
 <span id="case-bezel-crystal-and-crown-notes"></span>
@@ Line 133: / Line 133: @@
 === Fixed bars ===
-Fixed bars are the key structural identifier. The strap bars are soldered permanently to the case rather than using removable spring bars, preventing accidental strap detachment underwater — a critical safety feature for military diving. The bars are sized for NATO-style fabric strap pass-through rather than standard Oyster bracelet attachment.
+Fixed bars are the key structural identifier. Strap bars are soldered permanently into the lugs rather than fitted as removable spring bars, so the strap cannot detach underwater if a bar fails. They are sized for NATO-style fabric pass-through and will not take a standard Oyster bracelet.
 <span id="minute-bezel"></span>
 === 60-minute bezel ===
-The 60-minute bezel carries minute gradations all the way around rather than just at five-minute intervals, giving the diver minute-by-minute elapsed-time tracking for decompression timing. It was a Ministry of Defence specification requirement and does not appear on any retail Submariner of the period.
+The 60-minute bezel carries minute gradations all the way around rather than only at five-minute intervals, giving the diver minute-by-minute elapsed-time tracking for decompression. It was a Ministry of Defence requirement and appears on no retail Submariner of the period.
 <span id="case-engravings-and-caseback-markings"></span>
 === Case engravings and caseback markings ===
-Military issue watches carry specific engravings on the caseback and between the lugs, varying by batch as described above. The primary authentication factor for any 5517 is the presence of correct, matching military markings.
+Military-issue watches carry specific engravings on the caseback and between the lugs, varying by batch as set out above. Correct, matching military markings are the primary authentication test for any 5517.
-Rolex Forum collectors frame the dual-engraving structure cleanly: "Rolex inside the caseback, Navy outside." Rolex reference and production markings appear on the inner caseback, while military identification — broad arrow, circled T, NATO stock numbers, and service numbers — appears on the outer caseback. This inside/outside split is consistent across all batches and is the first thing to check when evaluating a claimed 5517.
+The dual-engraving pattern splits cleanly between maker and customer. Rolex reference and production markings sit on the inner caseback. Military identification (broad arrow, circled T, NATO stock numbers, service numbers) sits on the outer caseback. The inside/outside split holds across all three batches and is the first place a serious buyer looks.
-The broad arrow is the British government property mark, stamped into the outer caseback and appearing on most 5517 examples. Any broad-arrow watch in the civilian market was either legitimately decommissioned through official channels or has an unclear chain of custody. Either history is possible, but the broad arrow itself is never a civilian or retail marking.
+The broad arrow is the British government property mark, stamped into the outer caseback and present on most 5517 examples. Any broad-arrow watch in the civilian market either left service through official decommissioning or carries an unclear chain of custody. The mark itself is never a civilian or retail marking.
-The circled T is the UK legal requirement under the Radioactive Substances Act for tritium-containing items. On most examples the circled T appears alongside the broad arrow, establishing both military ownership and regulatory compliance under British law.
+The circled T is the UK legal requirement under the Radioactive Substances Act for tritium-containing items. It typically appears next to the broad arrow, marking military ownership and regulatory compliance in the same engraving block.
-Many MilSub examples show a NATO stock number beginning with 0552, the Ministry of Defence procurement prefix, and a correctly formatted 0552 prefix is consistent with authentic MOD procurement. An individual service number or unit identifier is often engraved on the caseback, linking the watch to a specific sailor or diving unit. These numbers are the most useful provenance tool, and cross-referencing a service number against Royal Navy records where accessible is the most rigorous authentication available.
+Many examples carry a NATO stock number beginning 0552, the Ministry of Defence procurement prefix, and a correctly formatted 0552 number is consistent with authentic MOD procurement. An individual service number or unit identifier is often engraved alongside, linking the watch to a specific sailor or diving unit. Cross-referencing a service number against Royal Navy records, where accessible, is the most rigorous provenance check available for the reference.
 <span id="bracelets-end-links-clasps-and-packaging-notes"></span>
 == Bracelets, end links, clasps, and packaging notes ==
-Military-issue watches were delivered on NATO-style fabric straps rather than metal bracelets, consistent with the fixed-bar design. The fixed bars are not compatible with standard Oyster bracelet attachment, and the NATO strap pass-through design is deliberate: the strap continues beneath the watch even if one bar fails, preventing loss of the watch underwater. Packaging followed procurement logistics rather than retail presentation. Watches were delivered in military stores packaging, not standard Rolex retail boxes.
+Military-issue watches were delivered on NATO-style fabric straps rather than metal bracelets, in keeping with the fixed-bar design. The bars do not take a standard Oyster bracelet, and the NATO pass-through is deliberate: the strap continues beneath the watch even if one bar fails, so the watch stays on the wrist. Packaging followed procurement logistics. Watches arrived in military stores packaging, not standard Rolex retail boxes.
 <span id="special-branches"></span>
@@ Line 166: / Line 166: @@
 === Batch 3 broadsword ===
-Third-batch broadsword-hand examples are the most collected and most valuable 5517 variant. The combination of dedicated 5517 engravings, broadsword hands, fixed bars, and 60-minute bezel represents the full-specification MilSub in its most complete form.
+Third-batch broadsword examples are the most collected and most valuable form of the reference. Dedicated 5517 engravings, broadsword hands, fixed bars, and the 60-minute bezel are the full-specification MilSub in one watch.
 <span id="batch-1-transitional"></span>
 === Batch 1 transitional ===
-First-batch examples with 5513 engravings show the 5517 before it developed its own identity. They represent the earliest military-specific Submariners in the 5517 program.
+First-batch examples with 5513 engravings show the 5517 before it developed its own caseback identity. They are the earliest military-specific Submariners in the 5517 programme.
 <span id="authentication-warning"></span>
 == Authentication warning ==
-The 5517 is one of the most faked Rolex references in existence. The combination of extreme value (consistently above $200,000 at auction), a relatively simple base watch (modified 5513), and the difficulty of verifying military provenance creates a powerful incentive structure for fraud.
+The 5517 is one of the most faked Rolex references in the market. Extreme value (consistently above $200,000 at auction), a comparatively simple base watch (a modified 5513), and the difficulty of verifying military provenance combine to make the reference a fraud target.
-The conversion path is straightforward: take a standard 5513, add fixed bars, swap to a 60-minute bezel, engrave military markings on the caseback, and fit broadsword hands. Each modification is technically achievable by a skilled watchmaker. The result can be visually convincing to anyone who has not handled genuine examples.
+The conversion path is short: a standard 5513 takes fixed bars, a 60-minute bezel, military caseback engravings, and broadsword hands. Each step is within reach of a skilled watchmaker, and the finished result can be visually convincing to anyone who has not handled a genuine example.
-Rolex Forum collectors stress three checks on any 5517 purchase. Provenance verification — a documented chain of custody connecting the watch to a specific Royal Navy unit or service number, verifiable against accessible military records. Physical inspection by a specialist who can read fixed-bar construction, caseback engraving depth and consistency, bezel graduation quality, and hand proportions against genuine military specification. Cross-referencing against known examples — with only about 180 accounted for in collector databases, the community of 5517 specialists is small enough that most genuine examples are tracked.
+Three checks carry most of the authentication weight. First, documented provenance: a chain of custody connecting the watch to a specific Royal Navy unit or service number, verifiable against military records where those records are accessible. Second, physical inspection by a specialist who can read fixed-bar construction, caseback engraving depth and consistency, bezel graduation quality, and hand proportions against genuine military specification. Third, cross-reference against known examples; with only about 180 accounted for, the specialist community is small enough that most genuine watches are tracked.
-The fake 5517 problem is not theoretical. Rolex Forum collectors have documented specific examples of fraudulent conversions appearing at auction and through private dealers. The authentication burden should be treated as the most important step in any 5517 transaction.
+The fake problem is not theoretical. Specific fraudulent conversions have been documented at auction and through private dealers, and authentication should be treated as the load on any 5517 purchase.
 <span id="historical-market-and-auction-record"></span>
 == Historical market and auction record ==
-Three major auction results establish the 5517 as a consistent six-figure reference across different examples.
+Three auction results frame the 5517 as a consistent six-figure reference across different examples.
-At Sotheby's in November 2023, a 5517 MilSub c.1978 sold for 482,600 CHF and reset the auction ceiling for the reference. That result is now the clean market anchor for a full-spec late watch.
+Sotheby's, November 2023: a MilSub c.1978 sold for 482,600 CHF and reset the auction ceiling for the reference. That result is now the reference point for a full-spec late watch.
-Sotheby's November 2018: a 5517 c.1978 sold for 218,750 CHF, documented with caliber 1520, military issue numbering, and a Rolex presentation case. Estimate was 150,000–300,000 CHF.
+Sotheby's, November 2018: a 5517 c.1978 sold for 218,750 CHF, documented with caliber 1520, military issue numbering, and a Rolex presentation case, against an estimate of 150,000 to 300,000 CHF.
-Sotheby's December 2019: a 5513/5517 c.1974 sold for $262,500. The lot bridges the 5513 and 5517 designations, consistent with the transitional Batch 1 and Batch 2 examples where 5513 and 5517 markings coexist.
+Sotheby's, December 2019: a 5513/5517 c.1974 sold for $262,500. The lot bridges the 5513 and 5517 designations, consistent with the Batch 1 and Batch 2 examples where 5513 and 5517 markings coexist on one caseback.
-Three auction results above $200,000 in their respective currencies, across a five-year window, for a watch produced in roughly 1,200 units with only 180 accounted for. The scarcity arithmetic is simple and severe. 180 documented out of approximately 1,200 produced means the majority of MilSub production is destroyed, lost, or sitting undiscovered. Unlike a rare vintage complication where production numbers are uncertain, the MilSub's rarity is structural. It was made for one client, in limited procurement batches, to be used operationally. Most of these watches had hard lives.
+Three results above $200,000 in their respective currencies, inside a five-year window, for a watch produced in roughly 1,200 units with only 180 accounted for. The rarity is structural rather than statistical. It was made for one client, in limited procurement batches, to be used operationally, and most of these watches had hard lives.
-The value drivers are distinct from ordinary vintage scarcity. A 5517 commands prices above $250,000 because it concentrates several things at once: genuine military provenance (not a retailer's stock watch), period-correct tritium lume aged naturally over five decades, physical specification unavailable on any retail watch (fixed bars, 60-minute bezel, broadsword hands), and the weight of British naval diving operations during the Cold War era. Each factor independently adds value; together they produce results that consistently exceed pre-auction estimates.
+The value drivers are also specific. A 5517 reaches prices above $250,000 because it carries genuine military provenance rather than retail stock, period-correct tritium lume aged naturally across five decades, and physical specification unavailable on any retail watch (fixed bars, 60-minute bezel, broadsword hands). Each factor adds value on its own; together they produce results that regularly clear pre-auction estimates.
-The market runs on batch type, completeness of military documentation, and physical condition. Third-batch broadsword examples in full-specification condition with documented military provenance — service number on caseback, matching inside number, original T SWISS T dial with unpolished case — represent the peak of the MilSub market.
+The market runs on batch type, completeness of military documentation, and physical condition. Third-batch broadsword examples in full-spec condition, with documented provenance, the service number on the caseback, the matching inside number, and an original T SWISS T dial in an unpolished case, sit at the top of the MilSub market.
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