The Audemars Piguet Royal Oak Perpetual Calendar Openworked ref. 26585CE.OO.1225CE.01 has a 41 mm black ceramic case and the self-winding Calibre 5135. Self-winding Calibre 5135, 40 h power reserve; Functions: perpetual calendar with week indication, day, date, astronomical moon, month, leap year, hours and minutes; Case: Black ceramic case, glareproofed sapphire crystal and black ceramic caseback, screw-locked crown. Diameter 41 mm, thickness 9.9 mm, water resistant to 20 m; Dial: sapphire dial, smoked external zone of the counters, pink gold applied hour-markers and Royal Oak hands with luminescent coating, black inner bezel; Black ceramic bracelet with titanium AP folding clasp. Full set. Maker: Audemars Piguet. Reference: 26585CE.OO.1225CE.01. Available through ELITA's private desk — verification review, discreet handling and storage. Price on request. Case Size: 41mm. Case Material: Black ceramic case. Movement: Automatic — Calibre 5135. Dial: Sapphire dial, smoked external zone of the counters, pink gold applied hour-markers and Royal Oak hands with luminescent coating, black inner bezel. Bracelet/Strap: Black ceramic bracelet with titanium AP folding clasp. Complications: Perpetual calendar with week indication, day, date, astronomical moon, month, leap year, hours and minutes.