Audemars Piguet · Automatic

AP 5909

A variant of calibre 5900, the movement Audemars Piguet introduced in 2022 for the 37 mm Royal Oak. The 5909 leaves out the date, which makes it the first self-winding hours, minutes and seconds calibre the company has built at this diameter. Against the 3120 it replaces it is thinner — 3.9 mm rather than 4.26 — and runs at 4 Hz instead of 3, while holding a longer reserve.