Rolex Sea-Dweller DEEPSEA Steel — D-Blue Dial | Ref. 136660

The Sea-Dweller DEEPSEA Ref. 136660 is Rolex's most extreme expression of professional dive watch engineering, built to withstand the pressures of the ocean's deepest trenches. The 43 mm Oystersteel case incorporates the patented Ringlock System — a structural armature comprising a nitrogen-hardened steel ring, a domed 5 mm sapphire crystal, and a solid titanium case back — enabling water resistance to an extraordinary 3,900 metres / 12,800 feet. This is not a specification for divers alone; it represents a statement of absolute mechanical confidence.

Calibre 3235 powers the DEEPSEA with the full force of Rolex's contemporary movement programme. The movement features the Chronergy escapement — a nickel-phosphorus lever and escape wheel geometry that increases energy efficiency by 15% — alongside a Parachrom hairspring in Rolex's proprietary blue paramagnetic alloy for superior anti-magnetic and shock resistance. With 70 hours of power reserve, it surpasses most dive complications on the market. COSC chronometer certification confirms rate accuracy of -2/+2 seconds per day.

The D-Blue dial — a gradient wash running from deep black at the outer edge to luminous Rolex blue at the centre — was created to honour James Cameron's record-setting 2012 Mariana Trench dive, accompanied by a DEEPSEA prototype. It evokes the transition from abyssal darkness to surface light in a single glance. Chromalight luminescent hour markers and hands provide long-duration blue-glow legibility at depth, while the unidirectional rotating black Cerachrom bezel with 60-minute graduation stands ready for decompression timing.