Audemars Piguet 25820 Royal Oak Perpetual Calendar 18K Yellow Gold / Champagne (25109)

25109 Audemars Piguet 25820 Royal Oak Perpetual Calendar, 18k yellow gold case and yellow gold bracelet is in excellent condition, automatic Audemars Piguet perpetual calendar caliber 2120/4, day, date, month, moonphase, gold dial with applied gold stick numerals, sapphire crystal, diameter 39mm, thickness 10mm, Like New with original box and papers dated Jan / 1993.

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This watch is in stock and available for purchase at our retail showroom in Boston.

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More about Audemars Piguet 25820 Royal Oak Perpetual Calendar 18K Yellow Gold / Champagne

This is an 18k yellow gold Audemars Piguet Royal Oak Perpetual Calendar 25820. It has an integral 18k yellow gold bracelet with a double deployment clasp, and a scratch resistant sapphire crystal. The 39mm diameter solid three-body case is polished and brushed, with a sapphire display case back secured by 8 hexagonal screws. It has a flat octagonal bezel secured by 8 hexagonal white gold screws, and correctors on the case band at 4, 8, and 10 o'clock. The dial is champagne with gold Royal Oak baton hands and hour markers, with an outer minute track. It has a subsidiary dial for the days of the week at 9 o'clock, a sub dial at the 3 o'clock position for the days of the month, and one for the months at 12. There is a moon phase and leap year sub dial at 6 o'clock, all with blued hands. It's water resistant to 50 meters/150 feet, and it has a 40-hour power reserve. The 10mm thick case, dial, and movement are all signed.

The automatic self-winding Audemars Piguet ultra-thin caliber 2120/4 movement is rhodium-plated. It's constructed with 38 jewels, 343 components, and a shock absorber mechanism. The balance has variable inertia blocks, with the frequency of the balance wheel at 19,800 vph. It has a mobile stud balance spring holder, and a 21K gold oscillating weight segment. It has bidirectional winding and a self-compensating flat balance spring. There is a suspended barrel, and the shake of the oscillating weight is precise with an annular ring that runs on four jewels. The bridges are hand polished, with polished bevels, satin-brushed edges, and perlage on the recesses. There is a straight-line lever escapement, and a Gyromax balance adjusted to heat, cold, isochronism and 5 positions. It includes a hand-engraved and skeletonized rotor with a 21K gold segment. The Moon phase is constructed with physical vapor deposited with metal onto sapphire.

Audemars Piguet introduced the Gerald Genta-designed Royal Oak in 1972. It was named for the oak tree in which Charles II of England hid from his enemies, the Roundheads. In 1978, they developed a new version of their 1950 perpetual calendar watch with a movement that self-adjusted until the year 2100.