Rolex Datejust 31 mm

Rolex Datejust 31 mm, reference 278384RBR-0016, comes in a 31 mm case of steel and gold. The case carries a diamond-set bezel and a sapphire crystal with a Cyclops lens over the date. Inside is the calibre 2236, a self-winding movement with a Syloxi hairspring and a power reserve of approximately 55 hours; Rolex certifies it as a chronometer. The silver dial has luminous hands and indices and a central seconds display, with a date window under the Cyclops lens. Diamonds also appear elsewhere on the watch. A steel bracelet closes with a concealed folding clasp finished in steel and gold. The screw-down crown helps keep the case waterproof to 100 metres.