Deepsea 126660 (2018-2022)

The Deepsea is Rolex's 3,900-meter diving watch. Reference 126660, introduced in 2018, revised the model that had first appeared ten years earlier. It kept the 44-millimeter steel case and extreme depth rating, while adding calibre 3235 and changing the proportions of the lugs and bracelet.

Its size is not explained by the movement alone. The Ringlock case structure places a strong internal ring between a very thick sapphire crystal and the case back. Under pressure, those parts carry the load around the mechanism. The domed crystal is 5.5 millimeters thick—thicker than some complete dress watches.

Rolex offered the 126660 with a black dial or the D-blue treatment that grades from blue at the top to black below. The latter had first appeared in 2014 to commemorate James Cameron's descent into the Mariana Trench. It is a visual reference to the loss of light underwater.

The 126660 was not the experimental watch attached to Cameron's submersible, and it arrived years after the expedition. Its blue-black dial commemorates the event; it does not inherit the prototype's history.

The 2018 changes were practical developments within the existing design. The new movement extended the running reserve to approximately seventy hours. The broader bracelet and revised case attachments changed the proportions around the same 44-millimeter diameter. The depth rating did not increase.

There is a great deal of writing around the dial, including the names of the gas-escape valve and Ringlock system. It makes the Deepsea less visually quiet than a Submariner. That conspicuous frame, however, points to the actual subject of the watch: the structure surrounding an otherwise familiar display of time and date.