The Rolex Deepsea reference 136660-0006 is a professional dive watch featuring a 44mm Oystersteel case and an intense black dial. Engineered for extreme depths, it utilizes the Rolex Ringlock System and a helium escape valve to achieve a water resistance of 3,900 meters. The watch is equipped with a 5.5mm-thick domed sapphire crystal and a unidirectional rotatable bezel with a black Cerachrom ceramic insert. It is powered by the self-winding caliber 3235 movement, which offers a 70-hour power reserve and a precision of -2/+2 seconds per day. The timepiece is paired with a three-link Oyster bracelet featuring the Glidelock extension system for fine adjustments over a diving suit.
In terms of complications, the watch provides central hours, minutes, and seconds, along with an instantaneous date display at the 3 o’clock position. Unlike many other Rolex models, the Deepsea does not include a Cyclops magnification lens over the date to maintain the structural integrity of its thick crystal. The dial is finished with a Chromalight display, using luminescent material on the hands and indices that emits a long-lasting blue glow for visibility in dark underwater environments.
General reviews highlight the 136660 as a technical masterpiece that refines its predecessors by slimming the bezel and slightly enlarging the date window for better legibility. While critics often note its substantial thickness of 17.7mm and significant weight, many collectors appreciate its imposing wrist presence and the engineering required to withstand immense pressure. The removal of the Fliplock extension in this reference has been a point of discussion among enthusiasts, but the overall consensus remains that it is one of the most capable mechanical dive watches ever produced.