The Rolex Sea-Dweller Deepsea 126660-0002 was introduced at BaselWorld 2018. This second-generation of the Deepsea features a redesigned case & bracelet, and is powered by Rolex' caliber 3235 rather than the 3135 found in the first generation.
Calibre 3235 is a new generation movement, entirely developed and manufactured by Rolex for a superlative level of performance. Certified as a Swiss chronometer by COSC (Swiss Official Chronometer Testing Institute), it is tested a second time by Rolex after being cased to ensure that in everyday use it satisfies Rolex’s criteria for precision, which are twice as exacting as those for an officially certified chronometer. This control of the final precision of the assembled watch is carried out using a methodology and high-technology equipment specially developed by Rolex. Caliber 3235 features the new Chronergy escapement and Parachrom hairspring.