A "skindiver" is a case design, not a complication. The lugs are an integral part of the case and read as a natural continuation of the watch head, so the case, bezel and lugs appear machined from a single piece. The case runs 36 to 39 mm, and both case and bezel sit slimmer than the watches that came after it. Any complication can live inside that case: the 1957 Model 60 is time-only, and the Deepstar chronographs share the identical skindiver case.
Aquastar’s signature on the skindiver was the friction ring. The click spring had not been invented yet, so bezels of the period turned freely in both directions and could be knocked out of position mid-dive, which makes a bezel worse than useless: it reads wrong. Aquastar fitted a friction ring between the case and the bezel to hold it against accidental rotation. That is what made the Model 60 a serious dive instrument rather than a watch with a bezel on it.
The mechanism is Swiss patent CH 335178, Pièce d’horlogerie à lunette tournante, filed on 17 December 1957 by JeanRichard® S.A., Genève, with Fred Byrde named as inventor, granted 31 December 1958 and published 14 February 1959. The claim is specific: an open wire ring seated in a groove between the case body and the bezel, pressing radially through its own undulations to create une friction empêchant la lunette de tourner intempestivement, a friction preventing the bezel from turning inadvertently. It was filed in the Model 60’s own year, and it predates every other patent in the Aquastar archive. The defining specifications: 36 to 39 mm case diameter, lugs integral to the case rather than soldered or screwed on, a slim bezel, and 50 to 100 m water resistance. The complication is irrelevant to the classification. The rotating-bezel dive watch took shape around 1953; Aquastar's 1957 Model 60 became one of its definitive examples, and Aquastar's next move reshaped the category, turning the time-only skindiver into a wrist-worn dive instrument.
The skindiver era
Before the 1960s there was no industry standard for what made a dive watch a dive watch. Each Swiss maker decided independently. The result was a category called "skin-divers": watches built for free divers and for the new recreational scuba (the Aqualung, Cousteau and Gagnan's open-circuit demand regulator, had only existed since the 1943 patent).
The skindiver era has no hard edges, it fades rather than ends. It opens in 1953 with the first watch built to a written specification for an actual military diving unit (a Swiss-made model issued to the French Combat Swimmers). It closed in the mid-1960s, when the "professional" dive watch consolidated around a larger 40 mm case and 200 m water resistance, specifications that have defined the category ever since.
What makes a watch a skindiver
- Diameter: 36 to 39 mm. The Aquastar Model 60 was 37 mm. Most of its contemporaries sat in the same range; the few outliers reached 41 mm.
- Water resistance: typically 50 m, sometimes 100 m. Modern divers find these depths laughable, but a 50 m skin-diver was significantly more water-resistant than every dress watch sold at the same time.
- Bezel: slim 60-minute elapsed-time, bidirectional on the earliest examples because the click spring had not been invented yet. Some used the internal-compressor system patented by Ervin Piquerez in 1956, a second crown at 4 o'clock rotates an internal ring.
- Movement: typically a hand-wound calibre, Aquastar used the FHF 96/97 in the early Model 60s, then transitioned to AS-1700 automatics by 1962.
- Crystal: almost always acrylic Plexiglas (mineral glass arrived later, sapphire later still).
The 1957 Aquastar Model 60
Frédéric Robert's first dive watch shipped in 1957 with a 37 mm cushion case (the corners of the square chamfered into the round bezel, a defining mid-century shape) and a bidirectional 60-minute bezel. It was 100 m water-resistant. Don Walsh wore one on the bathyscaphe Trieste's 1960 descent to Challenger Deep, 10,916 meters. The watch came back up working. Read Don Walsh's Aquastar story.
The modern Model 60 was a true re-creation of the 1957 original, faithful down to the bidirectional bezel, a period limitation that existed only because the click spring had not yet been invented. The Model 60 MKII corrected that quirk, replacing it with a practical unidirectional bezel. It keeps the same 37 mm cushion case off the original 1957 drawings, modernised with a sapphire crystal and a Sellita SW200-1 in Elaboré grade. See the current Model 60 collection.
Buying a vintage skindiver today
Authentic 1957 to 1965 skindivers from the surviving makers of the era trade in narrow ranges, with Aquastar Model 60 at the more accessible end (EUR 2,500, 6,500 depending on dial condition and originality). Comparable Swiss skindivers from other 1950s manufacturers reach from low four-figures up into the deep five-figures for the most celebrated references.
The single biggest factor in valuation is dial originality. A relume, re-applied luminous paint, drops a watch's value by 40, 60%. Acrylic crystals get polished; that's fine. Hands get replaced; that's not fine but reversible. Case re-finishing is the silent killer, once the original brushing is gone, no restoration brings it back.
Frequently asked questions
What is a skindiver watch?
A skindiver is a small-cased dive watch from the late 1950s and early 1960s, built before the modern dive-watch standard was written in 1996. The defining specifications are a 36 to 39 mm case, lugs integral to the case, a slim bezel, and 50 to 100 m water resistance. The complication is irrelevant, the Deepstar chronographs use the same skindiver case.
Who made the first skindiver watch?
The rotating-bezel dive watch emerged around 1953 from several Swiss makers. Aquastar's own skindiver, the 1957 Model 60, is one of the category's definitive examples: a 37 mm cushion-case watch with 100 m water resistance. Aquastar's lasting contribution came next, turning the skindiver into a dive instrument with the 1959 Navigator and the patented no-decompression bezel.
What's the difference between a skindiver and a modern dive watch?
Skindivers are smaller (36 to 39 mm versus 40+ mm), rated to lower depths (50 to 100 m versus 200 to 1,000 m), and use acrylic crystals rather than sapphire. The push past 300 m began in the late 1960s, and cases grew with the ratings rather than with the seriousness of the diving.
Why are skindiver watches small (36 to 39 mm)?
The mid-century Swiss watchmaking standard for a man's wristwatch was 36 to 38 mm, and the early dive watches were built on the same case sizes as the rest of the catalogue. The larger 40 mm+ case did not arrive because divers became more professional. A skindiver is a professional instrument. It arrived because of the depth race: 500 m, then 1,000 m, and eventually the 3,900 m Rolex Sea-Dweller Deepsea and the 11,000 m Deepsea Challenge. Deeper ratings force thicker crystals, heavier cases and bigger bezels. The skindiver did not become less serious. It stayed the size the work required.
Can I buy a modern skindiver?
Yes. The Aquastar Model 60 MKII is a direct reissue of the 1957 original, built from the same archive drawings with a 37 mm cushion case, and a sapphire crystal over a Sellita SW200-1 Elaboré movement. See the current Model 60 collection.
JeanRichard® is a trademark of its respective owner. Aquastar is not affiliated with, endorsed by, or sponsored by it. Historical references on this page describe the Geneva workshop that was renamed Aquastar S.A. in 1962.
Related reading: Aquastar Model 60, the modern skindiver reissue · Don Walsh and the Aquastar on the Trieste · Dive-watch glossary
