Rolex Sea-Dweller

Rolex Sea-Dweller
is a professional dive watch designed for saturation diving in extreme, high-pressure environments. It was created in 1967 and features a helium escape valve (HEV) to release excess gas built up during deep-sea dives. Modern models are known for their exceptional water resistance, durability, and a blend of tool-watch utility with luxury finishing.


Design and features
According to Rolex's website, the Sea-Dweller's design is defined by its robust construction and specialized diving features:


Case: The Oyster case is crafted from a single block of highly corrosion-resistant Oystersteel. Modern standard Sea-Dweller cases are 43 mm in diameter.

Bezel: The unidirectional rotatable bezel features a 60-minute graduated Cerachrom insert, a scratchproof and fade-resistant ceramic material. Its knurled edge provides a firm grip, even when wearing gloves.

Bracelet: The Oyster bracelet features a patented Oysterlock safety clasp to prevent accidental opening. It also incorporates a Rolex Glidelock extension system, allowing for micro-adjustments for a perfect fit over a diving suit.
Helium escape valve (HEV): This proprietary feature, patented in 1967, automatically releases helium molecules that penetrate the watch case during deep-sea saturation dives. This prevents the crystal from being blown out by internal pressure during decompression.

Chromalight display: The dial's hands, hour markers, and bezel are filled with a luminescent material that emits a long-lasting, bright blue glow for excellent legibility in low-light conditions.

Cyclops lens: Introduced to the standard Sea-Dweller model in 2017, this magnifying lens on the sapphire crystal enlarges the date display for improved readability. Early models and the Deepsea variant intentionally do not have a Cyclops lens, as it was thought to compromise pressure resistance at extreme depths.