At 31 mm, the Datejust 31 wears the hallmark Oyster architecture: a monobloc middle case, solid case back, and screw-down winding crown operating through the Twinlock double waterproofness system, delivering water resistance to 100 metres. The round case and matching Jubilee bracelet — composed of five-piece links in Everose Rolesor — fasten via a concealed folding Crownclasp, while a scratch-resistant sapphire crystal with a Cyclops lens over the date window keeps the dial legible at a glance.
The rosé dial presents Roman numeral hour markers, with the large VI position set with 11 diamonds, lending measured brilliance without overwhelming the overall composition. Framing the crystal, the bezel is fully set with diamonds, completing the jewellery-forward character of reference 278381RBR-0002.
Inside runs the Rolex Caliber 2236, a perpetual mechanical self-winding movement with bidirectional winding via the Perpetual rotor and a power reserve of approximately 55 hours. The oscillator employs a Syloxi silicon hairspring with patented geometry alongside Paraflex shock absorbers, achieving a precision of -2/+2 seconds per day after casing. Functions include centre hour, minute, and seconds hands, instantaneous date with rapid setting, and stop-seconds for precise time setting.
