Vacheron Constantin Traditionnelle complete calendar openface

The Traditionnelle complete calendar openface, reference 4020T/000G-B655, is a 41mm round case in white gold with a grey dial and sapphire crystal. It is fitted with the automatic Vacheron Constantin calibre 2460 QCL/2, which drives date, weekday, month, and moon phase displays, and includes a display back. The piece carries the Poinçon de Genève, or Hallmark of Geneva, a certification introduced by the Republic and Canton of Geneva in 1886 to denote quality craftsmanship and provenance in fine watchmaking.