The ultra-resistant divers’ models engineered by Rolex for the conquest of the deep: waterproof to a depth of 4,000 feet (1,220 metres) for the Rolex Sea-Dweller and 12,800 feet (3,900 meters) for the Rolex Deepsea, they are the result of decades of collaboration with diving professionals.
The dial is the distinctive face of a Rolex watch, the feature most responsible for its identity and readability. Characterised by hour markers fashioned from 18 ct gold to prevent tarnishing, every Rolex dial is designed and manufactured in-house, largely by hand to ensure perfection. The dial of the new Sea-Dweller carries the model’s name in red, a reference to the first model.
The Sea-Dweller’s 60-minute graduated, unidirectional rotatable bezel enables divers to safely monitor their dive and decompression times. It is equipped with a patented black Cerachrom bezel insert manufactured by Rolex in a virtually scratchproof ceramic whose colour is unaffected by ultraviolet rays. The graduation is coated via PVD (Physical Vapour Deposition) with a thin layer of platinum. The sleek black dial features large Chromalight hour markers and hands filled with luminescent material that emits a long-lasting blue glow for excellent legibility in dark conditions.
Before they return to the open air, professional divers heading for the surface after a deep saturation dive must spend time in a decompression chamber, where they breathe a gas mixture containing helium. The tiny molecules of helium, an extremely light gas, infiltrate into the watch. During decompression, the helium is unable to escape from the waterproof case quickly enough, creating a pressure differential that could force the crystal out of the watch case. Rolex engineers created a gas escape valve fitted with a spring: it opens when the difference in pressure between the inside and outside of the watch reaches 3 to 5 bars, allowing the helium to escape, thereby protecting the watch.
The patented Rolex Glidelock extension system allows divers to adjust the length of the bracelet for a secure and comfortable fit over a diving suit, without using any tools. A robust toothed panel under the clasp cover provides an extension of up to 20 mm in 2 mm increments.
The robust 44 mm case in Oystersteel, thick domed sapphire crystal and unidirectional rotatable bezel with a 60-minute graduated black Cerachrom insert exude the purposeful character of the Rolex Deepsea. It is the uncompromising divers’ watch, built for the most demanding underwater missions. In 2014 Rolex announced the release of the Rolex Deepsea D-blue Dial, commemorating James Cameron’s historic solo dive to the bottom of the Mariana Trench, some 11,000 metres deep. From twilight blue to bottomless black, its two-colour gradient dial celebrates one man’s journey to the deepest place on earth.
The Rolex Deepsea owes its exceptional strength, waterproofness and pressure resistance to the exclusive Ringlock system. This innovative case architecture patented by Rolex enables the watch to resist the massive pressure exerted by water at the depth of 3,900 metres (12,800 feet), equivalent to a weight of approximately 3 tonnes on the watch. Its construction is based on three elements: a nitrogen-alloyed steel central ring forms the backbone of the system, accompanied by a 5.5 mm‑thick, domed sapphire crystal and a case back in grade 5 titanium.
The case architecture that enables the Rolex Deepsea to resist the colossal pressure exerted by water at great depths takes advantage of two surprising features. First of all, the strong titanium case back is almost imperceptibly flexible thanks to the natural qualities of the alloy, making it extremely resilient to such huge forces. Secondly, the water pressure itself forces the three core components of the Ringlock System, including the case back, tighter and tighter together as the depth increases, naturally reinforcing the hermetic seal of the case.