THE ESSENTIALS

MAKE: ROLEX
MODEL: 1665
YEAR: 1976
BOX/PAPERS: NO/YES (service papers)
CASE DIAMETER: 40mm
CASE MATERIAL: STAINLESS STEEL
BRACELET MATERIAL: STAINLESS STEEL
MOVEMENT: AUTOMATIC

The Sea-Dweller is, to this day, the only Rolex sports model born out of pure necessity. Unlike the MilSub—which was effectively an altered 5513—the Sea-Dweller was created because the dive watch Rolex had at the time simply wasn’t capable of keeping up with the rapidly evolving world of sub-sea exploration.

In the 1960s, underwater research was developing at a remarkable pace. Rolex found itself in a horological race to the bottom, going head-to-head with Omega. They needed to produce the first professional dive watch—one that could be used by saturation divers routinely descending beyond 300 metres.

Omega won the initial battle with the Seamaster 600, or “Ploprof,” developed with assistance from Comex divers. But it’s fair to say Rolex won the war. Working with SEALAB divers—known as Aquanauts—in the US Navy, they first modified a 5513 to include a valve allowing helium to escape the case during decompression. It wasn’t entirely successful, which led to a completely new design and a new case architecture. By 1971, Rolex had formed a partnership with Comex after Omega’s relationship with the French diving company faltered. Rolex agreed to supply all watches to Comex for free in exchange for detailed real-world testing and reporting.

Reference 1665 was produced from 1967 to 1983 (with the “Red” variants specifically between ’67 and ’77), though the model did not officially retail until 1971; most watches made prior to ’71 were not intended for civilian use.

This particular example is the most common variant, the Mk4. This dial type is seen between the 3.0m and 5.2m serial range, with this watch falling at 4.1m.

The dial is the star of the show here, the markers have a deep and rich patina with no staining, the hands appear to be slightly later, changed at service but still show some creaminess. The bezel is a Mk3 as people call it with the regular 5, bang on for this generation. Its has some wear as you would expect. The date wheel is the correct brushed silver wheel. The case has been polished in the past, Rolex would have certainly valeted the case when it went in for service The 93150 bracelet is A coded denoting it was made in 1976. 

The watch comes with several service receipts from Rolex, as far back as the early 90's and as recent as the mid 00's. Previously owned by a Hyperbaric Medical Offer in Scotland, the caseback engraving is in the exact front Rolex used for the Comex engravings. Pretty cool.

Based on the number of London Rolex service engravings within the caseback, the watch has been looked after. The movement is running well at +5 secs per day, 265 amps with a 0.5 beat error. The watch flew through a 5 bar pressure test also. 

This is an extremely well priced example of an iconic and highly collectible watch.