The Rolex Sea Dweller was a purpose built watch for divers who needed a watch that could withstand the extreme pressures of deep sea diving. First produced in the 1967 it was originally water resistant up to 2000ft (610 meters). In 2000 the Sea Dweller was succeeded by the new model which has a new depth rating of 4000 ft (1220 meters).  The newest model now to come from Rolex is the Deep Sea 116660 which has a depth rating of 12800 ft (3900 meters). The helium escape valve on the side of the watch is a distinct feature which enables the watch to have such a high depth rating. The Rolex Sea has benefited from more than 30 years modification. With no Cyclops magnifier on the glass it has a distinct style.  As with all current models in production the Rolex Oyster range, the Sea Dweller is powered by a  self-winding  Rolex movement. Each movement has 100 points of contact with proprietary lubricants to ensure reliable performance.