The Audemars Piguet Royal Oak Selfwinding reference 15550ST.OO.1356ST.01 is a 37mm luxury sports watch released in 2022 to commemorate the 50th anniversary of the Royal Oak collection. This model features a stainless steel case with a thickness of 8.9mm to 9mm, which is thinner than its predecessors due to the integration of the new self-winding Calibre 5900. The watch is defined by its iconic octagonal bezel with eight hexagonal screws and a white “Grande Tapisserie” dial. The dial features white gold applied hour-markers and Royal Oak hands with luminescent coating, along with a date window at the 3 o’clock position. The branding is rendered in 24k gold through a galvanic growth process, replacing the previous printed logo for a cleaner aesthetic.
In terms of technical specifications, the Calibre 5900 movement operates at a frequency of 4Hz (28,800 vph) and provides a power reserve of approximately 60 hours. A distinguishing feature of this anniversary reference is the rhodium-toned 22k pink gold oscillating weight, which is openworked to display a “50 Years” logo, a detail exclusive to models produced during 2022. The watch is equipped with a stainless steel integrated bracelet that has been redesigned with thinner, lighter links and a more pronounced taper for improved ergonomics. The case is water-resistant to 50 meters and features a sapphire crystal and exhibition caseback.
General reviews of the 15550ST highlight its refined proportions and versatility as a unisex timepiece. Critics and enthusiasts often praise the subtle ergonomic updates, such as the enlarged bevels on the case and the more comfortable bracelet design, which allow the 37mm case to wear slightly larger than its dimensions suggest. The removal of the “Automatic” text from the dial is frequently noted as a move toward a more minimalist and modern look. While the watch is highly regarded for its exceptional hand-finishing and historical significance, some collectors mention the lack of a screw-down crown as a minor drawback for a sports-oriented timepiece, though it does not impact its stated water resistance for daily wear.