The Rolex Sea Dweller has a longstanding history that is deeply linked to deep-sea diving. It played an instrumental role in the research and development of the dive watch archetype that began sometime back in the 1950s. After the Second World War, leisure diving gradually grew in popularity, which in some ways, paved the way for such dive watches to be made commercially available for military, professional, as well as for civilian use.
In the following decade, when experiments involving saturation diving for commercial deep sea divers were carried out extensively, there was suddenly a need for watches with much greater water resistance. At the time, the standard issue Rolex Submariner was able to withstand 200m of pressure and water resistance, but Rolex set out to triple those numbers. Eventually came the Sea-Dweller Ref. 1665 “Double Red” in 1967, which featured an impressive 610m of water resistance and cutting-edge technology that predominantly revolved around the helium escape valve (HEV).
Fast forward half a century later, the Sea-Dweller has evolved into a model that sits at the top of the professional line of Rolex sports models, and what we have on offer here today is one such example – the Rolex Deepsea Sea-Dweller Ref. 126660.
First introduced in 2018, the Ref. 126660 represented Rolex’s ongoing efforts in over-engineering their famed dive watch design, something the Crown has been known to do. In some ways, I’d say that the Ref. 126660 is somewhat like the G-Wagen of Rolex; it is big, built like a tank, and yet very seldom (as far I am aware) pushed to its limits by its respective owners.
As far as its specifications go, the Ref. 126660 features a case size of 44m x 18mm and a whopping water resistance of 3,990 meters (12,800 feet), which is more than triple in water resistance over its non-Deepsea counterparts. How did they do it? Well, this came as a result of incorporating several engineering marvels onto the Ref. 126660, such as the 5mm-thick sapphire crystal supported by a Ring Lock system as seen on the dial, a unidirectional Cerachrom bezel, and a helium escape valve on the left flank of the case.
On the dial, you will find a familiar configuration that is quintessentially Rolex; super-legible hands (and a Mercedes hour hand) and hour markers filled with blue Chromalight material for luminosity. There is also a subtle date window aperture at 3 o’clock which adds to the overall functionality of this beast.
Powering the Ref. 126660 from within is the upgraded self-winding Rolex Cal. 3235, an incredibly reliable chronometer-grade movement featuring Rolex’s Chronergy escapement and an impressive 70-hour power reserve. The solid caseback is made out of titanium which helps with weight management and ensures water resistance. Additionally, Rolex also included another impressive technical feat that is the 904L steel Oyster bracelet with Glidelock (Rolex’s sliding in-clasp extension) and Fliplock (Rolex’s wetsuit extension) extension systems, which makes it effortless to adjust, so it can be easily worn over a wetsuit.
Indeed, the Sea-Dweller may be considered by many as a niche model from Rolex, but I think it is important to remember that the Sea-Dweller belongs to Rolex’s top-of-the-line professional range; it was designed with an extremely pragmatic and technical purpose in mind. While it does not hold the universal appeal of a Daytona or a Submariner, the level of technical engineering that went into its design is still undeniably impressive, which makes it even more difficult to argue against it because it represents Rolex’s approach and philosophy when it comes to technical watch design.