The 1st Royal Oak styles were equipped with the calibre 2121 movement, which was based upon the calibre 2120 formulated by Audemars Piguet in 1967, the planet’s thinnest self-winding movement on the period with date indication, and an In general top of 3.05mm. The calibre 2121 was also Outfitted by https://www.watchesworld.com/frozen-in-time-luxury-watches-for-winter/