The main Royal Oak designs ended up fitted with the calibre 2121 motion, which was based upon the calibre 2120 created by Audemars Piguet in 1967, the entire world’s thinnest self-winding motion in the period with day sign, and an General top of 3.05mm. The calibre 2121 was also Geared https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/