Audemars Piguet Royal Oak Skeleton Openworked Skeleton Stainless Steel, Anthracite Grey Openworked Dial with Gold Applied Hour-Markers and Royal Oak Luminescent Hands, AP Calibre 3129 Self-Winding Automatic Movement, Skeleton Back, Stainless Steel Bracelet.

The 39mm octagonal bezel is secured with 8 polished white gold face screws, and it has polished finished beveled corners. The 39mm solid three-body case, angled screwed lugs, bracelet, and flat, brushed bezel, are polished/brushed. The actual dial has an anthracite grey perimeter ring with a luminous white minute/second scale, luminous white gold hour pips, white gold baton hands with luminous inserts, and a center sweep second hand with a counter balance. It has a 60-hour power reserve at full winding, and it’s water resistant to 50 meters/165 feet. The 9.4mm thick case, dial, and movement are all signed. It has an integral stainless steel link bracelet with a double folding deployment clasp, and a scratch-resistant antireflective sapphire crystal. It has a screw-down hexagonal winding crown, and a screw-down exhibition sapphire display case back secured with 8 white gold screws.

This Audemars Piguet Royal Oak Skeleton Automatic 15305ST.OO.1220ST.01 has a mechanical automatic self-winding AP caliber 3129 movement. It’s completely openworked and rhodium-plated with hand finishing on the mainplate and bridges, which are brushed satin with a galvanic anthracite treatment. It’s constructed with 38 jewels, 239 components, a straight-line lever escapement, a monometallic Gyromax balance, and a shock absorber device. It includes a self-compensating flat balance spring with variable inertia blocks, a 22K gold rotor with ceramic ball bearings, and a hacking seconds device for precision time setting. The mechanism oscillates at a frequency of 21,600 vph (3 Hz).

Reference No. 15305ST.OO.1220ST.01