Vacheron Constantin Traditionnelle perpetual calendar ultra-thin

Vacheron Constantin's Traditionnelle perpetual calendar ultra-thin, reference 4305T/000G-H135, measures 36.5 mm across in white gold. The case stands just 8.43 mm thick, a slim proportion for a full perpetual calendar movement. A sapphire crystal covers the silver dial, and a matching sapphire caseback shows the calibre 1120 QP self-winding movement, carrying the Hallmark of Geneva and running with 40 hours of power reserve. Alongside the perpetual calendar, the dial carries a moon phase display, with date, day and month shown by hand. This watch is set with diamonds. Dark blue alligator leather closes on a white gold pin buckle. Water resistance is rated to 30 metres, adequate for a dress watch of this kind.