Vacheron Constantin Patrimony retrograde day-date

The Patrimony retrograde day-date, reference 4000U/000R-B516, has a 42.5mm round rose gold case with a sapphire crystal and blue dial. It is powered by the automatic Vacheron Constantin calibre 2460 R31R7/3, offering 40 hours of power reserve and displaying retrograde date and weekday functions. The watch carries the Poinçon de Genève hallmark, a certification introduced by the Republic and Canton of Geneva in 1886 to denote quality craftsmanship in watchmaking. It has a water resistance of 30 metres and a display case back.