Audemars Piguet Royal Oak Openworked Perpetual Calendar 18K Yellow Gold FIRST SERIES


Audemars Piguet 25636 Royal Oak Openworked Perpetual Calendar, 25636BA.0.0344BA.01, 25636BA00344BA01, 18k yellow gold case with an integrated yellow gold bracelet (fully linked) is in excellent condition and has developed a rich patina, automatic Audemars Piguet perpetual calendar caliber 2120/2802 movement, transparent sapphire dial with yellow gold baton hands, day, date, month, and moonphase, sapphire crystal, display back, C series, diameter: 39mm, thickness: 9mm. Amazing First Series example 25636BA with winding box, service box, and extract from the AP Archive dated March of 1987. This watch was just completely serviced by AP.

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More about Royal Oak Openworked Perpetual Calendar 18K Yellow Gold FIRST SERIES

This is an 18K yellow gold Audemars Piguet Royal Oak Openworked Perpetual Calendar 25636BA.0.0344BA.01. It has an integral 18k yellow gold bracelet with a folding deployant clasp, and a scratch resistant sapphire crystal. It has an octagonal winding crown, and there are three correctors in the case bands for the perpetual calendar, including two on the left and one more on the right. It includes an octagonal beveled exhibition sapphire display case back secured with 8 screws, and it's engraved with "AUDEMARS PIGUET SWISS MADE – QUANTIEME PERPETUEL AUTOMATIQUE," and a serial number. The 39mm diameter solid three-body case, bracelet, hooded angled lugs, and flat, polished-edge beveled bezel with 8 hexagonal white gold face screws, are brushed/polished. The dial is rhodium plated with skeletonized components, yellow gold baton hands, and there is a gold perimeter minute scale. The moon phase subsidiary dial at 6 o'clock is created with Physical Vapor Deposited metal on sapphire, and there are three slightly smaller champagne gold rimmed subsidiary dials with black Arabic numerals and letters, and blued indicator hands, including a day register at 9 o'clock, a date dial at 3 o'clock, and a month dial at 12 o'clock. The gold of this watch has a rich patina making it seem more rose than yellow. It has a 40-hour power reserve at full winding, it's water resistant to 20 meters/67 feet, and the 10mm thick case, dial, and movement are all signed. This Audemars Piguet Royal Oak Openworked Perpetual Calendar 25636BA.0.0344BA.01 has a mechanical automatic self-winding Audemars Piguet caliber 2120/2802 (base Audemars Piquet caliber AP2121) perpetual calendar movement. It's rhodium plated with Cotes de Geneve and perlage embellishment, and hand engraving, and it's constructed with 38 jewels, 343 components, a straight-line lever escapement, and an anti-shock device. It includes a Gyromax type monometallic balance that's adjusted to heat, cold, isochronism, and 5 positions a self-compensating flat-balance spring, a mobile balance spring stud holder, and variable inertia blocks on the balance spring. The 21K gold rotor segment is skeletonized and hand engraved, and the mechanism oscillates at a frequency of 21,600 vph (3 Hz). The Audemars Piguet Royal Oak Openworked Perpetual Calendar 25636BA.0.0344BA.01 was first introduced in 1983.

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