The Rolex Sea-Dweller 126603 “Two-Tone” marries deep-sea capability with refined elegance. Its 43 mm Oyster case combines corrosion-resistant 904L steel with 18k yellow gold accents—most notably the unidirectional bezel and winding crown. The black dial features bold luminescent hour markers and hands engineered for underwater legibility, while the date window at 3 o’clock retains the Sea-Dweller’s tool-watch heritage. Rated to 1,220 m water resistance, the 126603 retains serious diving capability yet delivers a more elegant demeanor thanks to its gold elements.