Reference:3666
Submarine → 3666
The 3666 is a pre-Oyster. Before Rolex settled on the three-piece screwed case that defined everything from late 1926 onward, Wilsdorf was already selling waterproof wristwatches under a name the modern collector will find startling: Rolex Submarine. The trademark was registered on 31 March 1922, thirty-one years before the 1953 Submariner dive watch picked it up again, and with no historical continuity between the two. The 3666 is a documented example of that earlier Submarine line, dated 1924, built on Jean Finger’s Swiss patent CH 89276 for a hermetic double case. It is the direct operational precursor to the Oyster and, by most accounts of those who have handled one, the reason the Oyster had to be invented.
Core facts
| detail | value |
|---|---|
| reference | 3666 |
| family | Submarine / Hermetic (pre-Oyster) |
| production | ~1924 onward (patent architecture from 1921) |
| case construction | double case — one-piece outer with screw-down bezel, separate inner movement case with no stem hole |
| case diameter | 32.35 mm overall (Boettcher measurement of a documented Hermetic) |
| movement diameter | 21 mm (9.3 ligne, nominal “9½”) |
| case materials | sterling silver (most common), 9ct pink gold, 18K gold |
| case markings | “JF / Double Boitier Brevet 89276” — Jean Finger, Longeau, Berne |
| inner caseback | signed W&D (Wilsdorf & Davis) |
| crown/winding | pendant winder on inner case; outer case must be unscrewed to access |
| trademark | “Rolex Submarine” — Swiss registration 31 March 1922 |
| British patent | GB 197208 “Improvements in and Relating to Watches,” priority 26 May 1922, granted 10 May 1923 (Wilsdorf, no credit to Finger) |
A second, entirely different watch also carries reference 3666 — a 1940 Valjoux-22 antimagnetic chronograph. It is addressed at the end of this article. Everything above this paragraph refers to the 1924 Hermetic.
Where it sits in the line
The 3666 is the production expression of an architecture Rolex did not invent. The hermetic double case originated in the workshop of Jean Finger at Longeau, in the Bernese Jura, who filed Swiss patent CH 89276 (“Montre à remontoire avec boitier protecteur,” a keyless watch with a protective outer case) in January 1921. Finger’s idea was simple and brutal. Sealing a winding crown against water was difficult. So do not seal the crown; seal the entire watch. Put the movement inside a small inner case with no stem hole and no opening back, then enclose that inner case inside a one-piece outer case sealed by a screw-down bezel. To wind or set the watch, unscrew the outer bezel, lift out the inner case, operate its pendant winder, then reassemble. The result is genuinely waterproof, because there is no crown to leak through. The price is that every daily interaction with the watch requires two-piece disassembly.
Wilsdorf saw what Finger had built and commercialized it. On 31 March 1922 he registered the trademark “Rolex Submarine” in Switzerland, a Rolex-branded version of the Finger hermetic. The following year, on 10 May 1923, the British patent office granted Wilsdorf GB 197208, “Improvements in and Relating to Watches,” with a priority date of 26 May 1922. GB 197208 describes the same double-case architecture as CH 89276. It does not credit Finger by name. The surviving cases, however, all carry the marking “JF / Double Boitier Brevet 89276,” for Jean Finger’s initials, his French-language phrase for the double case, and his patent number. All Hermetic cases in the Rolex retail chain were made in Finger’s workshop under the CH 89276 monopoly. Boettcher’s research treats the GB/CH divergence as an ownership ambiguity, not a factual dispute. The architecture is Finger’s. The retail brand is Rolex’s.
Production of ref 3666 runs from approximately 1924 onward. The reference is part of the broader Rolex “Hermetic” catalog, which Wilsdorf also marketed under the “Submarine” name and under several alternate brands (Aqua, Oyster Watch Co. antecedents) in parallel, the same architecture re-badged for different retail channels. The Hermetic line ends once the Oyster three-piece case is commercialized in late 1926. The Oyster, with its sealed crown, one-piece disassembly for service, and daily winding through a screw-down crown rather than an unscrewed outer shell, obsoletes the double case immediately. Nothing about the Hermetic architecture survives into later Rolex production. What does survive is the trademark: the “Rolex Submarine” registration of 1922, dormant for three decades, is the name that returns in 1953 on a very different watch.
The double-case architecture
The 3666 is two watches, one inside the other. The outer case is a round steel or precious-metal shell, approximately 32 mm across, with soldered wire lugs and a smooth body. Its top is a heavy screw-down bezel that closes onto the outer case’s main body through a fine thread, sealed by a flat mineral crystal. Unscrewed, the bezel lifts away and exposes the second watch inside: a small, complete inner case of roughly 21 mm diameter, containing the movement. This inner case has no crown pendant in the conventional wristwatch sense — winding is accomplished by a small pendant winder at the top of the inner case, accessible only after the outer bezel is removed. The inner case has no opening back. The movement is permanently sealed inside it. For service, the inner case must be opened by a watchmaker through the same pendant-end access used for winding, or physically cut open.
The inner caseback, where visible after disassembly, is typically signed W&D — the mark of Wilsdorf & Davis, the firm’s legal name in Britain before the 1919 rebrand to Rolex. W&D stamps appear on Rolex-era pieces into the mid-1920s as a legacy supplier convention; on the Hermetic, they confirm the inner case originated in the Wilsdorf retail chain rather than through a third-party assembly.
There are no crown guards. There is no screw-down crown in the Oyster sense. There is no gasket at any winding or setting interface, because there is no winding or setting interface at all while the watch is assembled. The seal is entirely at the outer bezel thread and the outer case body join. For its era, this made the Hermetic genuinely waterproof in a way the contemporary stem-sealing efforts of Borgel and Taubert were not; the absence of a stem is stronger than the best stem seal. For any practical daily use, it is almost unusable. Time must be set by disassembly. The watch must be wound by disassembly. Reassembly requires precision threading of a small bezel onto a small case, with the inner case correctly re-seated inside the outer. The operation was awful. Wilsdorf knew it. Within five years he would commission the Oyster.
Dimensions
The single most carefully measured Hermetic in the published record is the vintagewatchstraps.com example documented by David Boettcher: outer case 32.35 mm overall, inner movement 21 mm, caliber 9.3 ligne (commonly rounded as “9½ ligne” in period sources). Other surfaced examples include a 33 mm sterling silver Hermetic with a white enamel dial and a 9ct pink gold “Officer’s watch” configuration dated 1924. The 32–33 mm outer diameter places the Hermetic at the larger end of early 1920s wristwatches, but the visible dial area is constrained by the need to fit the smaller inner case inside. The actual dial of a 3666 is a 21 mm disc set into a 32 mm shell, with the outer case ring visible as a broad bezel around it.
Dial and hand variants
Surviving 3666 dials fall into a narrow range, consistent with short production and consistent Finger-supplied casework. Confirmed configurations include:
White enamel with black Arabic numerals and subsidiary seconds at 6 o’clock. The most commonly surfaced dial on silver-cased Hermetics, including the Cargills Ceylon 1924 example sold by Bold Timepieces. Blued steel spade or Breguet hands.
Silvered metal with painted Arabic numerals and a sector sub-seconds register at 6. A slightly later treatment, consistent with mid-1920s dress-watch design language, surfaced on both silver and gold Hermetics.
Black dial with luminous radium Arabic numerals and cathedral hands. Documented on the 9ct pink gold “Officer’s watch” variant dated 1924, the configuration most clearly aimed at the military and field-service market the Hermetic name was meant to suggest.
There is no Rolex wordmark styling of the “Submarine” trademark on any known 3666 dial. The Submarine name appears in trademark filings and period marketing material, not on the dials of the watches themselves, which read simply “Rolex” above the sub-seconds register. This is consistent with 1920s Rolex practice: the model trademarks were retailer-facing and legal-facing, not dial-facing, and would remain so until the Submariner dive watch of 1953 put the name back on the dial.
The Cargills Ceylon example
The best-documented surviving 3666 is a 1924 sterling silver Hermetic retailed by Cargills Ltd. Ceylon, the Colombo department store that distributed Rolex across the British colonial market in the 1920s. It surfaced publicly through Bold Timepieces. The case is hallmarked silver, case markings include the Finger patent text (“JF / Double Boitier Brevet 89276”), the inner case is signed W&D, the dial is white enamel with black Arabic numerals and subsidiary seconds at 6. The watch is presented as a working example of the architecture — outer case unscrews, inner case lifts out, movement winds through the pendant of the inner case.
The Cargills retail signature places the watch in the early 1920s colonial supply chain that Rolex used for India, Ceylon, Singapore, and Hong Kong — a route that would matter again twenty years later when wartime contracts for the Bombay Presidency passed through the same network. The 1924 dating is the standard Cargills period; company records tie the Rolex distribution agreement to that decade.
Auction and dealer record
The 3666 has no deep auction history at the major houses, which is typical for Rolex references of the pre-Oyster period — too early, too small, and too operationally awkward to hold broad modern appeal. The watch’s public-market trail runs through specialist dealers and smaller lots at the major houses:
Bold Timepieces — 1924 Rolex Submarine Hermetique ref 3666 in silver, Cargills Ceylon retail signature. The best-documented surviving example and the anchor citation for the architecture in the modern dealer record.
Bonhams, Sale 29150, Lot 48 — Rolex Hermetic Submarine, dated c.1925. One of the only appearances of a 3666 at a named international house.
Connoisseur of Time — “1924 Rolex Submarine Full Hermetic Pre-Oyster,” surfaced as dealer stock with documentation of the CH 89276 patent lineage.
Mokum Watches — Hermetic Submarine “Aqua” listing, representing one of the alternate-brand Hermetic configurations that share the Finger architecture. Aqua-branded examples are technically not 3666 by catalog reference, but they share the double-case construction and reach the market through the same dealer channels.
The market for the early Hermetic is a niche inside a niche. Examples in good condition with original enamel dials trade modestly compared to later Rolex sport references — the absence of any dive heritage, any chronograph complication, or any auction-house framing narrative keeps prices well below what the historical significance might suggest. A collector buying a 3666 is buying a documentary object, not a performance piece.
The 1940 reference 3666 chronograph
Rolex reused the reference number. In 1940, the firm fitted a Valjoux-22 antimagnetic chronograph movement into a completely different case and stamped it ref 3666. Phillips has sold that watch under catalog number CH080216 for CHF 162,500. It is a waterproof-cased chronograph with a tachymeter scale, pump pushers, and a round steel case in the 35–37 mm range, visually and mechanically unrelated to the 1924 Hermetic. The two watches share nothing but the four-digit reference.
The reuse pattern is standard for Rolex of the 1920s–1940s: four-digit references were assigned as new cases entered the catalog, and once a case was discontinued its number could be reassigned to a later, unrelated watch. The Hermetic 3666 fell out of production by the late 1920s when the Oyster obsoleted the architecture; the number sat unused for over a decade before being applied to the 1940 chronograph. Any dealer listing for a 3666 should be cross-checked against the movement: a 9½-ligne Hunter-type caliber with no chronograph function, encased in a hermetic double case, is the 1924 Submarine; a Valjoux-22 chronograph in a single-piece waterproof case is the 1940 reference. These are two different watches with the same catalog number, and the shared number is the only thing they share.
Collecting considerations
Case markings are primary. A genuine 3666 Hermetic inner case carries the Finger patent text “JF / Double Boitier Brevet 89276” visibly on either the outer case flank or inside the outer bezel. The inner caseback carries W&D. Both markings should be present. Cases lacking the Finger patent text are either from a different Hermetic variant or from a Wilsdorf alternate-brand Hermetic (Aqua, pre-Oyster brand experiments) that shared the architecture but not the Rolex retail chain.
Enamel condition. White enamel dials on silver Hermetics are brittle and vulnerable to hairline cracks across nearly a century of survival. Original enamel with no cracks is exceptional and commands a meaningful premium. Small hairlines around the subsidiary seconds or near the dial feet are typical and not disqualifying; full cracks across the dial face or significant chipping are. Refinished enamel dials exist but are difficult to execute convincingly, and a re-enameled Hermetic is usually detectable under strong light.
Operational condition. A 3666 that no longer disassembles cleanly — outer bezel seized onto the outer case body, inner case corroded into the outer shell — is a substantial service problem. The bezel threads are fine and old; cross-threading a repair attempt can destroy the waterproof seal that was the entire point of the architecture. A working disassembly, with the outer bezel turning smoothly onto the outer body and the inner case seating correctly, is evidence of competent prior servicing.
Movement integrity. The inner case has no opening back. Access to the movement is through the pendant winder end only. A 3666 with a modified inner case — any evidence of cutting, flat-backing, or case alteration for service access — has been substantially compromised relative to original Finger construction. Original inner cases with intact W&D stamps and original pendant-winder access are the benchmark.
Price anchoring. The public market for the 3666 is thin enough that price anchoring is approximate. Surfaced examples in good enamel condition with clean case markings trade in a range that reflects their documentary significance rather than broader collector enthusiasm: well below the prices reached by even mid-range Oyster references of the 1930s, and a very long way below the 1940 Valjoux chronograph that shares the reference number. The historical significance is real; the market valuation is not yet aligned with it.
What the 3666 established
Three things survive from the Hermetic era into the Rolex canon.
Waterproofing as a design priority. Before the 3666, no wristwatch manufacturer had committed seriously to sealing against water; the dominant position was that waterproofing was a pocket-watch problem that did not apply to wristwatches. Finger solved it brutally. Wilsdorf saw the solution, licensed the case, registered the Submarine trademark, and put the first genuinely waterproof Rolex wristwatches onto the British and colonial markets through 1922 and after. Everything that follows (the 1926 Oyster, the 1927 Gleitze Channel swim on ref 34075, the 1953 Submariner dive watch) is downstream of this commitment.
The Submarine name. Registered on 31 March 1922 and held in reserve for thirty-one years before the dive watch picked it up again. The trademark survived corporate reorganization, the Oyster transition, and the Second World War. The 1953 Submariner did not arrive out of nowhere; its name was sitting in the Rolex trademark portfolio from the previous decade.
The lesson about daily use. The Hermetic is the counter-example that justified the Oyster. Wilsdorf commissioned the Perregaux-Perret screw-down crown, the Spillmann three-piece case, and the Aegler movement integration because the Finger double case, however waterproof, had made itself a daily annoyance. The Oyster is what a watchmaker builds after three years of selling Hermetics and learning what the customer actually wants. Without the 3666, there is no Oyster; with the 3666, the Oyster is inevitable.
Still open
The full Hermetic catalog
The 3666 is the best-documented of the Rolex Hermetic references, but it is not the only one. Period Rolex catalogs list Hermetic variants in multiple case materials and sizes, and the complete reference catalog for the Hermetic line has not been published in modern collector literature. Surfaced examples are consistent with a multi-reference catalog spanning silver, 9ct gold, 18K gold, and mixed-metal cases across ladies’ and men’s sizes. Systematic cross-referencing of surfaced cases against period Rolex dealer documents remains to be done.
Production totals
No production-total figure has been surfaced for the 3666 or for the Hermetic line overall. Finger’s workshop at Longeau was small, and the patent monopoly means every Hermetic case passed through that single supply chain. The total for the entire Hermetic catalog is likely low four digits across all references and materials, but this is inference from the small surviving corpus rather than documented production figures. The Jean Finger firm’s records, if they survive, would settle the question; they have not surfaced in published sources.
The GB 197208 / CH 89276 question
The relationship between Wilsdorf’s British patent and Finger’s Swiss patent is documented by Boettcher as an ownership ambiguity. Whether Wilsdorf paid Finger a license fee, purchased rights under a private agreement, or simply filed a British counterpart without Swiss licensing is not recorded in the surfaced primary sources. The fact that all surviving cases carry Finger’s patent number and initials suggests some form of acknowledged licensing arrangement, but the commercial terms are unknown.
The Wilsdorf alternate brands
Wilsdorf marketed Hermetic architecture under several brand names in parallel with Rolex (Aqua, proto-Oyster-era experiments, and retail-channel-specific brands that surface occasionally in dealer listings). The exact roster of alternate Hermetic brands, and their relationship to the Rolex Submarine catalog, is not fully documented. This reflects a general feature of early Wilsdorf retail strategy: multiple brands, shared supply chain, retail-channel segmentation. The pattern applies to the Hermetic era as much as to the contemporary Oyster and Rolco output.
Sources
- VintageWatchStraps (Boettcher) — hermetic
- Bold Timepieces — 3666 cargills
- Bonhams — 29150 lot48 hermetic
- Connoisseur of Time — of time hermetic
- Mokum Watches — hermetic submarine aqua
- Phillips — 3666 valjoux chronograph
- Wind Vintage — The Oyster Story (Part 1) — Owen Lawton / Wind Vintage, Wind Vintage
- The Vintage Rolex Field Manual, Chevalier Edition — unknown, Morning Tundra