Rolex Datejust 31 mm

The Rolex Datejust 31 mm, reference 278240-0013, comes in Oystersteel with a case measuring 31 mm across. The bezel is domed, and the case holds a scratch-resistant sapphire crystal with a Cyclops lens over the date. Behind the pink dial runs the calibre 2236, a self-winding movement built in-house with a power reserve of approximately 55 hours. Rolex certifies this piece as a chronometer, and the screw-down crown adds a further layer of security to the movement. The dial shows a central seconds hand alongside the date. It is fitted to a steel Oyster bracelet with a folding Oysterclasp, which includes the Easylink comfort extension for a better fit. The crown's screw-down system helps keep the case waterproof to 100 metres.