Audemars Piguet 2120

The Audemars Piguet 2120 is an automatic movement introduced in 1967. Measuring just 2.45mm thick, it is based on the Jaeger-LeCoultre 920 and was also used by Vacheron Constantin and Patek Philippe. Operating at 19,800 vph with a 40-hour power reserve and 36 jewels, it features sweep seconds and no date. The caliber powered Royal Oak references including the reference 5402, and remains a landmark ultra-thin automatic despite being discontinued.