Originally designed for the pioneers of professional deep-sea diving, the Sea-Dweller 4000 is equipped with one of the inventions that contributed to its stature: the helium escape valve, patented by Rolex in 1967. This ingenious safety valve releases helium from the watch case as the gas expands during the decompression phases of deepwater saturation dives, while preserving the waterproofness of the watch.

CERAMIC BEZEL INSERT AND LONG-LASTING LUMINESCENT DISPLAY

The Sea-Dweller 4000’s 60-minute graduated, unidirectional, rotatable bezel enables divers to precisely and 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.

THE OYSTER CASE, SYMBOL OF WATERPROOFNESS

The Sea-Dweller 4000’s Oyster case, guaranteed waterproof to a depth of 1,220 metres (4,000 feet), is a paragon of robustness and reliability. The characteristically shaped middle case is crafted from a solid block of particularly corrosion-resistant 904L steel. The fluted case back is hermetically screwed down with a special tool exclusive to Rolex watchmakers. The winding crown, fitted with the patented Triplock triple waterproofness system, screws down securely against the case, offering watertight security akin to a submarine’s hatch. It is protected by a crown guard that is an integral part of the middle case. The crystal is made of virtually scratchproof sapphire. The waterproof case of the Sea-Dweller 4000, housing its highprecision movement, ensures optimal protection from water, dust, pressure and shocks.

CALIBRE 3135, A SUPERLATIVE CHRONOMETER

The new Sea-Dweller 4000 is equipped with calibre 3135, a self-winding mechanical movement with a date display entirely developed and manufactured by Rolex. Like all Rolex Perpetual movements, the 3135 is a certified Swiss chronometer, a designation reserved for high-precision watches that have successfully passed the Swiss Official Chronometer Testing Institute (COSC) tests. Its architecture, like that of all Oyster watch movements, makes it singularly reliable. The oscillator, the true heart of the watch, has a blue Parachrom hairspring patented and manufactured by Rolex in an exclusive alloy of niobium and zirconium. Insensitive to magnetic fields, the Parachrom hairspring offers great stability when exposed to temperature variations and remains up to 10 times more precise in case of shocks than a traditional hairspring.

ADJUSTABLE BRACELET WITH SAFETY CLASP

The Sea-Dweller 4000’s Oyster bracelet is equipped with an Oysterlock safety clasp that prevents accidental opening, and with a double extension system that allows the watch to be worn comfortably over a diving suit up to 7 mm thick. The Fliplock extension link extends the bracelet by 26 mm, while the Rolex Glidelock system allows fine adjustments of the bracelet length in 2 mm increments for a total of approximately 20 mm. Neither of them requires the use of tools.