Automatic mechanical movement, Calibre AP 4401 (note: corrected common misnomer to reflect standard naming), column wheel mechanism with automatic winding capability and hacking seconds feature. Blue dial featuring luminous coating for hour markers and hands ensures excellent legibility in low light conditions. Fixed bezel crafted from rose gold-tone material with a case also made of 18kt rose gold, measuring 41mm diameter and 12.4mm thick. Sapphire crystal glass is scratch resistant and transparent to ensure clear visibility of the movement through an open sapphire back. Chronograph functions include three sub-dials displaying elapsed minutes (up to 30 minutes), elapsed hours (in a specific format - likely counting down from 12h for flyback function) and seconds, plus standard timekeeping with hour, minute, second display at 4-5 o'clock position. Includes date aperture. Water resistant up to 50 meters / 165 feet. Comes complete in original Audemars Piguet packaging including box, papers, warranty certificate, manual.