Deepwater Engineering The Sea-Dweller is designed for saturation diving, with a helium escape valve and robust construction. It reflects Rolexs commitment to technical innovation and underwater resilience. Classic Tool Watch This 1994 model features a 40mm Oystersteel case with a black dial and rotatable bezel. Powered by the calibre 3135 automatic movement, it offers a 48-hour power reserve. The Oyster bracelet is fitted with a Fliplock Oysterlock clasp, ensuring secure wear in demanding conditions.