Rolex 3135 is a calibre by Rolex.
The Rolex Calibre 3135, which in many different forms underlies all three-hand watches by Rolex, is designed, both in construction and also optically, for robustness, precision and long maintenance intervals. It has a few design quirks, such as red anodized components, a Breguet hairspring and a winding mechanism in which the axis of the weight segment is stored in synthetic ruby (normally the rotor mechanism is embedded in steel ball bearings).
The movement is installed in the models Datejust, Submariner Date, Yacht-Master and in the former model Sea-Dweller 4000, which was produced between 1988 and 2008. The successor Sea-Dweller Deepsea of 2008 also uses a 3135, but with new Parachrom blue hair spring.