This perpetual calendar chronograph from Patek Philippe briefly held the title for most expensive watch sold at auction when it went for 9.6 million Swiss francs at a Phillips Auction in Geneva in 2016. Dating to 1941, it is significant in several respects: the reference is the first wristwatch with both a perpetual calendar and chronograph, and it is one of only four total models made in steel — a complicated watch of any kind being an extreme rarity during the World War II years, when most steel was earmarked for the war effort. The 35mm case houses an extensively modified Valjoux caliber with exquisite Patek finishing.
