About the brand 

More than just the most recognized name in watches, Rolex has become one of the most recognized brand names period. Founded in 1905 by visionary businessman Hans Wilsdorf, Rolex’s pioneering legacy set the stage for all of modern watchmaking.

From the first automatic wristwatch to the first waterproof timepiece, there’s no shortage of innovations from the legendary watchmaker. In the 1950s, Rolex began designing tool watches for deep-sea diving, aviation, mountain climbing, and more. This trademark utility and consistency went on to become a signifier of luxury and prestige that persists to this day.

The history of the Sea-Dweller

The Sea-Dweller’s history is deeply linked to the history of diving on its own, and essential to the development of the dive watch that started in the 1950s. After WWII, leisure diving grew in popularity and due to demand, dive watches began to be commercialized for military, professional and civilian use.

The birth of the dive watch can be summed up by one timepiece, the Rolex Submariner, the world’s first commercially produced dive watch that was released in 1954, boasting a 100m water resistance (which later improved to 200m).

Then in the 1960s, experiments with saturation diving for commercial deep-sea divers had begun bringing about the need for watches with greater water resistance. At that time, the standard Submariner ref. 5513 could endure 200m of pressure but the goal of Rolex was to triple it. 

Experiments were carried by Rolex in collaboration with COMEX, the French deep-sea diving specialist, leading to the invention of a feature that would later become the hallmark of the Sea-Dweller: the helium escape valve.

The valve was first retrofitted on Submariner ref. 5514 watches made for COMEX, but in 1967, Rolex introduced the Sea-Dweller ref. 1665, the first watch designed with helium escape valve that was also available for civilian purchase.

The early models from 1967 – production was estimated to slightly over 100 pieces – were very similar to the Submariner ref. 5514 COMEX.

Key characteristics of the early Sea-Dwellers are a “double red” dial – having two lines of text on the dial in red print – along with “Submariner 2000” and “patent pending” engraved on the case back (as Rolex had then filed for, but had not yet received, the patent for the helium valve).

About the watch

At the BaselWorld watch and jewellery show 2008, Rolex introduced an updated Sea-Dweller model named the Rolex Oyster Perpetual Date Sea-Dweller Deepsea. Its reference number is 116660.

With an official depth rating of 3,900 metres (12,800 ft), the Sea-Dweller deepsea represented in its launch year the most water resistant mechanical watch in serial production. To obtain this official depth rating, the Sea-Dweller deepsea is tested to a depth of 4,875 metres (15,994 ft) to offer the 25% safety reserve required by the ISO 6425 divers' watches standard. To test the water resistance of the Sea-Dweller DEEPSEA, Rolex uses testing equipment developed for them by Comex. Normal surface air filled watch cases and crystals designed for extreme depths must be large to cope with the water pressure.

The Rolex Sea-Dweller deepsea watch case has a diameter of 44.0mm (1.73 in) mm and a thickness of 17.7 mm (0.70 in) (domed crystal thickness 5.5 mm (0.22 in)), and the case and bracelet weigh 212 g (7.5 oz).

Other features which came with the Deepsea at 2008 was the "Ringlock System" for sealing the sapphire crystal to the case, a caseback made of titanium/steel alloy, the "Glidelock-clasp" and diver extension link, "maxi-dial", engraved rehaut, ceramic bezel with platinum-filled numbers, calibre 3135 with antimagnetic Parachrome-Blue-hairspring and blue "Chromalight" loom.

The first variant of Sea-Dweller Deepsea reference 116660 has a classic black dial with white text on the dial.

A second "D-Blue"-variant was released in 2014 in honor of James Cameron and his journey to the deepest area of Earth's oceans in the year 2012. It has a blue/black dial and green colored "DEEPSEA"-label.

In 2018, the new Deepsea model reference 126660 was introduced at Baselworld. It was updated with the Calibre 3235, a broader bracelet, a resized folding clasp, and a slightly redesigned case.

Specifications