Then and Now: The First Rolex Sea-Dweller vs. The Current Sea-Dweller

In our latest chapter of our Then and Now series where we set out to compare the maiden model of a Rolex collection versus its newest edition, we’re diving into the Rolex Sea-Dweller. A professional dive watch born from a specific request from a commercial company that later became a favorite watch for the public at large, the Sea-Dweller has maintained most of its design over the course of its history with a handful of major modifications. Let’s find out more.

The First Rolex Sea-Dweller

Rolex Sea-Dweller Comex

Rolex launched the Sea-Dweller in 1967 at the request of Compagnie Maritime d’Expertises (COMEX), a French company specialized in engineering and deep diving operations. COMEX needed a professional dive watch to accompany their fleet of saturation divers and turned to Rolex to create one.

As a result, Rolex launched the Sea-Dweller ref. 1665 with a host of features for deep sea divers that went beyond the Submariner. The first notable detail is the watch’s water resistance rating of 610 meters (2000 feet), which was more than three times that of the 200-meter waterproof Submariner of the era.

Rolex Sea-Dweller 1665

The second important feature is the Sea-Dweller ref. 1665’s helium escape valve (HEV). To survive saturation diving, divers breathe a special mix of gasses. This can cause helium particles to build up within dive watch cases. Deep sea divers have to go through a period of decompression in hyperbaric chambers and due to the external pressure difference, the helium in the watch needs to escape—typically causing the crystal on top of the dial to pop off. To prevent this, Rolex fitted the Sea-Dweller ref. 1665 with a patented HEV mechanism to allow the helium to safely discharge from the watch without causing damage.

Another thing you’ll note with the inaugural Sea-Dweller is that although there is a date window, there is no Cyclops magnification lens on the thick acrylic crystal. This is because the protruding lens would not have been able to withstand the pressure of saturation diving.

Rolex Caliber 1575

The first Sea-Dweller ref. 1665 is often referred to as the Double Red Sea-Dweller or DRSD for short. This is simply because of the two lines of red text on the dial that read: SEA-DWELLER. SUBMARINER 2000.

The inclusion of the Submariner name on the dial reminds us that the Sea-Dweller ref. 1665 was essentially a heavily modified spin-off of the Submariner. Rolex made the Sea-Dweller dials with the red text for a decade until it was replaced with a dial with all white text in 1977.

Of course, as a dive watch, the Sea-Dweller 1665 includes plenty of lume on the dial and a rotating diver’s bezel with a black aluminum insert. The Sea-Dweller ref. 1665 runs on the self-winding Caliber 1575.

The Current Rolex Sea-Dweller

Rolex Sea-Dweller 126600

In a surprising move, Rolex discontinued the production of the Sea-Dweller collection in 2009 to make way for the even more robust Deepsea dive watch. However, in 2014 the Sea-Dweller reappeared yet again. Finally, in 2017 Rolex unveiled the most current edition with the Sea-Dweller ref. 126600. At a quick glance, the Sea-Dweller ref. 126600 may look quite similar to the very first Sea-Dweller ref. 1665—most notably, the return of the red Sea-Dweller text on the dial.

Yet, there are plenty of significant differences to highlight. Firstly, The Sea-Dweller ref. 126600 is the biggest version to date with a 43mm Oyster case rather than the previous 40mm sizes. As a result, the lug size also increased for proportional purposes.

Rolex Caliber 3235

Second, the sapphire crystal of the newest Sea-Dweller ref. 126600 now includes a Cyclops lens—yet another first for the Rolex Sea-Dweller line up. Additionally, the most current Sea-Dweller comes equipped with the new Caliber 3235 movement with a boosted power reserve of 70 hours and an improved accuracy rating.

Rolex Sea-Dweller 126600

The hands and indexes on the black dial glow blue in the dark thanks to the Chomalight luminescence, which was first introduced in the preceding Sea-Dweller ref. 116600. Plus, the Sea-Dweller ref. 126600 includes a Cerachrom ceramic bezel unlike the aluminum one of the first Rolex SD. It’s also worth mentioning that the Sea-Dweller has offered a 1,220 meter (4,000 feet) depth rating since the late 1970s, and the newest Sea-Dweller ref. 126600 retains that.

Furthermore, as a modern Rolex dive watch, the Oyster bracelet of the Sea-Dweller has the Glidelock extension system providing an extra 20mm in length. What’s more, as a professional dive watch, Rolex also includes the Fliplock extension system to lengthen the bracelet by an additional 26mm. When both systems are used together, the Sea-Dweller ref. 126600 can be worn over a very thick 7mm wetsuit.

The Rolex Sea-Dweller Evolution, Then and Now

While the Sea-Dweller first came out as an enhanced Submariner watch to suit the needs of pro saturation divers, today, the Sea-Dweller is very much its own Rolex model. This is especially true with the newest Sea-Dweller ref. 126600 given its larger case size and new movement.

Today’s Rolex Sea-Dweller remains true to the tool watch roots of the very first model, but in a more modern and bolder design.