Vacheron Constantin Patrimony retrograde day-date

Vacheron Constantin's Patrimony retrograde day-date, reference 4000U/000R-B516, is a 42.5 mm rose gold model. The case measures 9.7 mm thick and carries a sapphire crystal over a blue sunburst dial. Inside is the self-winding calibre 2460 R31R7/3, certified with the Hallmark of Geneva and giving 40 hours of power reserve. The retrograde day and date functions share the dial with central seconds, the day and date hands sweeping across their own arcs rather than sitting in windows. Through the sapphire caseback the finishing of the movement is visible. The watch is fitted to an alligator leather strap secured by a rose gold folding clasp. Water resistance is a modest 30 metres, enough for everyday wear but not for swimming.