This self-winding Audemars Piguet Royal Oak Openworked Perpetual Calendar is crafted from black ceramic and features both brushed and polished finishes. Measuring 41 mm in diameter with a thickness of 9.9 mm, it is both light yet highly resistant to scratches. The dial is skeletonised and features accents of pink gold, this includes the Royal Oak hands and applied hour markers, and the outer rings of the four subdials, these sub dials display the date, day, month/leap year and moon phase, and is protected by a glareproof sapphire crystal and a transparent caseback. The 26585CE.OO.1225CE.01 is powered by the self winding Manufacture caliber 5135 and provides functions that include a perpetual calendar with day of the week indication, date, astronomical moon, month, leap year, hours and minutes. Offering a power reserve of up to 40 hours, it is water resistant to 20 meters. This watch is accompanied by a brushed black ceramic bracelet with highly polished edges of the bracelet links and secured with a titanium AP folding clasp.