The 1st Royal Oak designs were being fitted with the calibre 2121 motion, which was based on the calibre 2120 designed by Audemars Piguet in 1967, the earth’s thinnest self-winding movement of your period with day indication, and an All round peak of three.05mm. The calibre 2121 was also Geared https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/