A true icon for divers and marine engineers, the Rolex Sea-Dweller is an outstanding diving watch,which water resistant up to 4,000 feet. 
Originally introduced in 1967, the Sea-Dweller was developed to increase the performances of the Submariner model pushing waterproofness to a depth of 610 metres initially and then to 4,000 feet in 1978. Thanks to the patented helium escape valve eliminating the excess helium, Rolex solved the problem that arises In habitats at overpressure, when the inner part of the watch case becomes saturated with this highly volatile gas as the pressure inside the watch case equalises with that inside the chamber.
The 40 mm satin finished steel case maintains the same proportion of the so-called “supercase” already introduced for the Submariner and GMT II models but it is thicker.The black satin-finished dial is the ideal background for the white gold hands and hour markers treated with Chromalight for long-lasting luminescence.
The unidirectional rotatable 60-minute graduated bezel is made of ultra-resistant black Cerachrom ceramic while the engraved numerals and graduations are coated with platinum via magnetron sputtering .
Other distinctive features of the new Rolex Sea-Dweller 4000 Ref. 116600 are the paramagnetic blue Parachrom hairspring used for the COSC-certified automatic movement and the Oysterlock folding safety clasp with Glidelock extension system.
