The 1st Royal Oak styles have been fitted Using the calibre 2121 motion, which was according to the calibre 2120 designed by Audemars Piguet in 1967, the globe’s thinnest self-winding movement of your period with day indicator, and an General top of 3.05mm. The calibre 2121 was also Outfitted using https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/