At 31 mm, this Datejust 31 wears a round Oystersteel case built around a monobloc middle with a screw-down case back and screw-down winding crown employing Rolex's Twinlock double waterproofness system, keeping the watch waterproof to 100 metres. A scratch-resistant sapphire crystal with a Cyclops lens over the date sits above the silver dial, which features a Chromalight display delivering long-lasting blue luminescence for excellent legibility. The domed bezel completes the case's clean silhouette.
The watch rides on an Oystersteel Jubilee bracelet composed of five-piece links and closes with a concealed folding Crownclasp. Inside beats the self-winding Calibre 2236 — a perpetual, mechanical movement manufactured by Rolex — offering a power reserve of approximately 55 hours and a precision rating of -2/+2 seconds per day after casing. The oscillator employs a Syloxi hairspring in silicon with patented geometry alongside Paraflex shock absorbers, and the movement carries Superlative Chronometer certification, reflecting both COSC testing and Rolex's own post-casing standards.
Functions include centre hour, minute, and seconds hands, an instantaneous date display with rapid setting, and a stop-seconds mechanism for precise time setting. Reference 278240-0006 represents the Datejust 31 in a versatile, sport-elegant configuration that transitions effortlessly across occasions.
