The original Rolex Sea-Dweller, created in 1967, was designed as a resilient and useful tool for professional deep-sea divers of that era. Among its many notable features was a helium escape valve, patented by Rolex that same year, which preserved the watch’s water-resistance while regulating the air pressure accumulated inside its case during the decompression phases of deep-water saturation dives.
The case of the new Sea-Dweller is 43 mm in diameter — 3 mm larger than its 40-mm predecessor. The scratch-resistant sapphire crystal over the deep black dial is equipped, for the first time on this model, with a Cyclops lens over the date window at 3 o’clock, enhancing its legibility. The text “Sea-Dweller” appears on the dial in red, echoing the look of the original 1967 model. Finally, the watch is equipped with the used Rolex Caliber 3235, a self-winding movement boasting a number of innovative technical details, some of them patented. This represents the first time Rolex has employed this recently introduced, technically superior movement in one of its “Professional grade” timepiece. Like all used Rolex watches for sale, this Sea-Dweller carries the Superlative Chronometer certification, instituted by Rolex in 2015, which ensures a high level of precision and timekeeping performance (-2/+2 seconds per day).
Like its most recent predecessors, the new Sea-Dweller is water-resistant to a depth of 1,220 meters (4,000 feet). Its 60-minute graduated, unidirectional, rotating divers’ bezel is fitted with a patented black Cerachrom bezel insert manufactured by Rolex in a virtually scratchproof ceramic whose color is unaffected by ultraviolet rays. The bezel’s graduations are PVD-coated with a thin layer of platinum. The dial’s large hour markers are filled with Chromalight, a Rolex-developed luminescent material that emits a long-lasting blue glow in low-light conditions.