The Rolex Oyster Perpetual Sea-Dweller Submariner 2000 that became available in 1967 was developed from the Submariner for the Comex S.A. industrial deep-sea diving company by increasing crystal thickness and was produced in several variations. It had a depth rating of 610 metres (2,000 ft) and its Rolex reference number was 1665.
Most Sea-Dweller watches incorporate a helium escape valve for saturation diving. Early Sea-Dwellers did not always have the helium escape valve. The model is also distinguished by the absence of the date magnifier ("cyclops") present on most other Rolex models. The Sea-Dweller diving watch range has been standard issue for Comex divers since 1977.