The Rolex Sea-Dweller introduced in 1971, is a heavier-duty steel version of the Submariner. The swiss rolex sea-dweller incorporates a helium escape valve for use with helium-based breathing gas mixtures in saturation diving; was superseded by the DeepSea Sea-Dweller in late 2008, with the last 16600 Sea-Dwellers produced running into the V-series. The DeepSea features a 44 mm case that guarantees a depth of 3,900 metres (12,800 ft). Although as rolex sea-dweller replica, it is also with a thicker case and crystal, as well as a date feature, sans Cyclops magnifier as the original. Learn More