Royal Oak Perpetual Calendar 25554 BA With Service, Extract from Archives, Certificate of Authenticity - Ref : 25654BA.OO.0944BA.01 - Full yellow gold 18k, first series of PC with ultra thin case (0.25mm less than ref 25654), perpetual calendar, moonphase, date, day, month, golden dial, applied stick markers, golden "sword-shaped" hands for the hour and blued for the calendar, automatic movement. With extract from the archives, certificate of authenticity, and full service from AP. Immaculate condition, a very important milestone for the AP PC.