AUDEMARS PIGUET ROYAL OAK PERPETUAL CALENDAR Reference: 25654ST. Serial No.: 769 / C94868. Stainless steel case. Light grey dial, featuring four sub-dials. Mechanical self-winding movement (calibre 2120/2800). Stainless steel bracelet with signed folding clasp. Sapphire crystal. Circa 1998. Diameter: 39 mm. Supplied with its original case and papers. A stainless steel wristwatch with an automatic movement, by Audemars Piguet. Circa 1998. An evolution of the 25554 model, the 25654 improves its water resistance by redesigning the case architecture, which slightly increases its thickness from 7.5 mm to 8.3 mm. 315 examples were produced between 1987 and 1998. Condition: Sold as is, with signs of wear and use. Movement was functioning at the time of writing this description; a routine service is recommended; no warranty provided.