Released in 2017, the Audemars Piguet Royal Oak Offshore Chronograph 44 ref. 26400IO.OO.A004CA.01 in titanium quickly became one of the hottest watches amongst AP lovers and without a doubt our favorite iteration of the Royal Oak Offshore 44 line. Fitted with a larger and more robust case than the original Royal Oak Offshore Chronograph line, the AP ROO Chrono ref. 26400IO measures 44 mm in diameter and 14.12 mm in thickness. Fitted with a titanium case and black ceramic bezel, this relatively newish reference brings to the 44 mm collection the only metal that was missing.