Additional Information: Harry Winston Ocean World Time Tourbillon gent’s watch, Model # 400/MATTZ45WL.A.18k White Gold 45mm round case. Bluish grey dial with dual time sub-dials, world city display and open tourbillon displays. Hours, minutes and seconds. Swiss automatic movement. Sapphire crystal front and back. Rubber strap with 18k white gold pin buckle. Water resistant up to 100 meters.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 and escapement rotate around their common axis going through all positions to average out the errors. Tourbillon cages or platforms usually rotate once per minute but 4 minute and six minute tourbillons are also found. The Tourbillon complication is an extremely difficult accomplishment to achieve and generally demands a high premium. Subject To Availability