Pre-owned Audemars Piguet Royal Oak ref 15510ST.OO.1320ST.08 is the successor to the ref. 15500 and nearly identical to the limited 50th anniversary edition released in 2022, without the commemorative rotor. Measuring 41mm in stainless steel, it features all the usual Royal Oak’s hallmarks: octagonal bezel with exposed screws, integrated bracelet, and the silvery “Grande Tapisserie” dial. The Royal Oak first debuted in 1972 with the now-legendary ref. 5402, featuring a bold 39mm case nicknamed “Jumbo.” From the 1980s to around the mid-2000s, AP trended smaller with the 36mm 14000 series, but the modern appetite for larger cases brought the 15000 series back to 39mm and 41mm, cementing the proportions we see today. This three-hander model embodies that evolution, complete with a highly sought-after silver dial.