A fine and extremely rare stainless steel automatic diver’s wristwatch with date, helium escape valve, and black dial bearing the COMEX logo. Made in the early 1980s, this example was supplied directly to the Compagnie Maritime d’Expertises (COMEX), the legendary French deep-sea diving company.

The present watch represents one of the most sought-after professional tool watches ever produced by Rolex. The reference 16660, also known as the “Triple Six,” marked an important evolution in the Sea-Dweller line, introducing a sapphire crystal, an increased depth rating of 1220 meters (4000 feet), and the robust Caliber 3035 with quickset date function.

This particular example, bearing the distinctive COMEX logo on the matte dial and the engraved caseback, was issued exclusively to professional divers employed by COMEX for deep saturation diving missions. These watches were never available to the public and were produced in extremely limited numbers, making them among the rarest and most coveted of all Rolex tool watches, with full serial engraved inside the caseback

Preserved in excellent overall condition, this Sea-Dweller COMEX ref. 16660 combines historical significance, technical innovation, and rarity, embodying the enduring partnership between Rolex and COMEX, one of the most fascinating collaborations in the history of professional diving instrumentation.