There may be no other vintage diver as storied and yet totally unsung as the original Deepstar, a dive chronograph optimized for legibility of one big-eye 30-minute register. Jacques Cousteau and his wife both wore a Deepstar for years, and one is pictured on his wrist for many of his filmed expeditions (most notably during The Undersea World). Freediver Jacques Mayol, too, wore one to time breath holds whilst apnea diving, and had one on wrist when setting a world record depth of 75m in 1968. While you do occasionally see vintage Deepstars surface on the secondary market, you almost never see them like this: a near perfect case, unrestored, undamaged dial, and on its original signed NSA spring-expansion diving bracelet.

Aquastar started in 1962 as the diving watch arm of the Jean-Richard Company, with a skin diver known as the 60. Interestingly, that 60 was worn on the very first descent to the bottom of the Mariana Trench. A Deep Sea Special was strapped to the outside of the bathyscaphe Trieste, but the veteran diver on the inside wore Aquastar. Then came the model 63 with a rotating bezel, which saw use in SEALAB. Finally, Aquastar culminated in this complicated diving chronograph, which was something of a halo-product.

The Deepstar design is eccentric in the extreme, with everything centered around one big-eye and an advanced rotating bezel. The left-hand register, with its parallelogram hand, is just a running seconds. Can you even call it seconds if it doesn't have a track? It's a 'this watch is running' register. Then you have a massively oversized 30-minute register for legiblity, very artfully designed 12-6-9 indices, and huge tritium hands. The whole design shouts 'I'm here for business'. Particularly the bezel, which not only tracks no-decompression stops for divers to avoid, well, exploding internally from expanding nitrogen fizz on ascent, but a residual nitrogen scale to help tell you how long to spend out of the water before you're safe to jump back in. The decimals effectively track the decreasing co-efficient of nitrogen in your body over time. Its design was the first of its kind, the only dive bezel more complicated and useful than Doxa's. This all rests in a 37mm steel case running a Valjoux 23.

You will find Deepstars with a variety of dial print for local markets, with branding such as Lorenz, Duward, or Jean-Richard. But the most desirable has always been the original flavor you see here, signed Aquastar, Deepstar, and 10 ATM (~100m). Because these were serious tools and almost always sold to actual divers in period, dials are rarely found looking anything like this: no visible moisture damage and faded to a dark tropic brown from grey.

Examples like this make me feel equal parts ecstatic and melancholy. While it's incredible to find one surviving in this state, it simply can't have been worn much in period given the condition. And I'm a fervent believer that all watches deserve to be worn. Nonetheless, perhaps it is actually for the better that one or two be left for future generations to appreciate in perfect detail, this is definitely that educational-level of condition. Despite that, I'm still hoping one of you, our readers, is going to love, treasure, and wear this museum Deepstar. Because connecting watches like this with enthusiasts like that, well that's what we're here to do.

This example is in exceptional overall condition, one the (if not the) best we've ever seen. To begin, the case is untouched, lightly worn, and seriously impressive. The back engravings are deep and even retain some of the black enamel, which we've never seen. There are a few marks on caseback and lug back from opening and strap changes. Its dial has a beautiful and honest patina, totally unrestored. These dials almost never age this gracefully, as these were often dived with. The dial is lightly showing signs of age but no damage, light spotting in the big eye and a textured patina that's, fittingly, almost stingray-like under loupe. The 5 index is very slightly darker in tone than the rest. But the all original tritium applications are all present and fade off evenly under UV. Best of all, it comes on its original NSA spring-expansion diving bracelet, which you almost never see. Serviced recently and running well. Of all Deepstars we've seen so far, this is the one.

This watch is modeled on a relatively large 7.7 inch wrist.

• Brand: Aquastar
• Model: Deepstar
• Reference: N/A
• Size: 37
• Year: c. 1965
• Case Material: Steel
• Movement: Manual Valjoux 23 Signed Aquastar
• Scope: Watch, Original NSA Bracelet, and Modern Aquastar Tropic Rubber Strap