ROLEX SEA DWELLER STEEL/GOLD 126603

It features a distinctive black dial and large luminescent hour markers. Waterproof to a depth of 4,000 feet (1,220 metres) with a unidirectional 60-minute rotatable bezel, the Rolex Sea-Dweller is amongst the ultra-resistant divers’ watches engineered by Rolex for deep-sea exploration.
The 60-minute graduated, unidirectional rotatable bezel of the Sea-Dweller enables divers to precisely and safely monitor their dive and decompression times. It is equipped with a patented black Cerachrom bezel insert manufactured by Rolex in a virtually scratchproof ceramic whose colour is unaffected by ultraviolet rays. The graduation is coated via PVD (Physical Vapour Deposition) with a thin layer of gold. The sleek black dial features large Chromalight hour markers and hands, filled with luminescent material that emits a long-lasting blue glow for excellent legibility in dark conditions.