The Audemars Piguet Royal Oak Perpetual Calendar (ref. 25654BA.OO.0944BA.01) represents a rare convergence of complication and design from the brand’s early QP lineage. Housed in 18k yellow gold with an integrated bracelet and gold-toned dial, this vintage reference channels Gérald Genta’s original Royal Oak form while embedding a full perpetual calendar within its iconic angular frame.

The 39mm case showcases the distinctive octagonal bezel with eight hexagonal screws and an ultra-slim yellow-gold profile of just 9.3mm. At its centre, a gold dial with applied indices and four subdials displays day, date, month, and a moonphase at 6 o’clock. Inside, the ultra-thin automatic calibre 2120/2800 delivers a full perpetual calendar function without compromising case thickness, boasting a power reserve of approximately 40 hours. Water-resistance is rated to 20m, marking it as more a connoisseur’s dress complication than a daily sports watch.

Produced in low numbers from the late 1980s through the early 1990s, the ref. 25654BA has become a pivotal piece for collectors of the Royal Oak’s complicated evolution—an emblem of how technical sophistication was fitted seamlessly into one of modern watchmaking’s most recognisable designs.