The Rolex Sea-Dweller Deepsea (Ref. 126660) is a professional-grade dive watch engineered for extreme depths up to 3,900 meters (12,800 ft). Featuring a 44mm Oystersteel case with a patented Ring Lock System and a helium escape valve inscribed 'ORIGINAL GAS ESCAPE', it ensures reliability during saturation diving. The black dial includes Chromalight luminescent hour markers and hands, a date window at 3 o’clock with Cyclops magnifier, and bold white numerals on the unidirectional Cerachrom bezel. Powered by the self-winding Caliber 3235 movement with Chronergy escapement, it offers ±2 sec/day precision and 70-hour power reserve. The Oyster Perpetual bracelet with Glidelock clasp allows micro-adjustment underwater. Housed in its original green Rolex box with warranty card (serial M646829), this timepiece embodies Rolex’s legacy of robust engineering and understated luxury—ideal for collectors, divers, and connoisseurs seeking horological excellence. Its rugged elegance suits formal events, business settings, or adventurous expeditions, bridging technical performance with timeless design.