Crafted in Yellow Rolesor — Rolex's combination of Oystersteel and yellow gold — the 31 mm Oyster case features a monobloc middle case, screw-down case back, and a screw-down Twinlock winding crown for water resistance to 100 metres. The bezel is set with diamonds, while scratch-resistant sapphire crystal with a Cyclops lens over the date adds both durability and legibility.
The olive green dial is itself set with diamonds, and a large VI marker is further adorned with 11 diamonds, lending the watch a distinctive, jewel-forward character. Bidirectional self-winding is handled by the Calibre 2236 Manufacture Rolex movement, which offers a Syloxi silicon hairspring with patented geometry, Paraflex shock absorbers, a power reserve of approximately 55 hours, and a precision rating of -2/+2 seconds per day after casing. The movement carries Superlative Chronometer status, reflecting both COSC and Rolex certification.
The three-piece solid-link Oyster bracelet is rendered in matching Yellow Rolesor and secures via a folding Oysterclasp with an Easylink 5 mm comfort extension link, allowing for easy on-wrist adjustment. Reference 278383RBR-0015 is presented as the Datejust 31, one of Rolex's most enduring designs.
