The 1st Royal Oak versions were equipped with the calibre 2121 movement, which was based on the calibre 2120 made by Audemars Piguet in 1967, the whole world’s thinnest self-winding movement of the era with day indicator, and an In general peak of 3.05mm. The calibre 2121 was also equipped https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/