Audemars Piguet Royal Oak Offshore Men’s Watch 43MM Stainless Steel Brown Rubber 26420SO. 100 m (10 ATM). The Audemars Piguet Royal Oak Offshore Chronograph with a brown dial is a must have for any fan of the brand. The stainless steel 43 mm case is assembled with a fixed, ceramic bezel and 40 jewels. This timepiece is powered by the 4401 calibre with a 70-hour power reserve.