Previously owned Audemars Piguet Royal Oak gent's watch, Model # 25977ST.OO.1205ST.02. Stainless steel 44mm x 58mm case with stainless steel crown and pushers. Stainless steel fixed bezel. Black colored dial with luminous index hour markers and hands. Hours, minutes, seconds, chronograph and tourbillon. Manual wind movement, AP Caliber 2889. Stainless steel bracelet with push button foldover clasp. Power reserve up to 70 hours. Water resistant to 20m or 60ft. Tourbillon

　　compensates for differences in rate caused by a watch adopting different positions. The principle is to mount the balance and escapement in a rotating cage. The balance & escapement rotate around their common axis going through all positions to average out the errors, Tourbillon cages or platforms usually rotate once per minute. The Tourbillon complication is an extremely difficult accomplishment to achieve and generally demands a high premium.

　　subject to availability