Reference 228398TBR-0006 presents the Day-Date 40 in a 40 mm monobloc 18 kt yellow gold case finished with a screw-down case back and a screw-down Twinlock winding crown for waterproofness to 100 metres. The bezel is set with diamonds, while a scratch-resistant sapphire crystal with a Cyclops lens magnifies the date display at a glance.
The silver dial carries Roman numeral hour markers and pairs with centre hour, minute, and seconds hands. Instantaneous day and date readouts appear in dedicated apertures with a secure rapid-setting function, and a stop-seconds mechanism allows for precise time setting. The 18 kt yellow gold President bracelet closes with a concealed folding Crownclasp.
Power comes from the Calibre 3255 perpetual, mechanical, self-winding movement — a Manufacture Rolex calibre featuring a paramagnetic blue Parachrom hairspring, high-performance Paraflex shock absorbers, bidirectional winding via a Perpetual rotor, a power reserve of approximately 70 hours, and Superlative Chronometer certification reflecting COSC testing plus Rolex certification after casing, achieving a precision of -2/+2 seconds per day.
