The Audemars Piguet Royal Oak Selfwinding reference 15550ST.OO.1356ST.06 is a 37mm luxury sports watch crafted from stainless steel, released as part of the collection’s 50th anniversary redesign. This model features a slim case profile of 9mm and a lug-to-lug distance of 46mm, making it a versatile unisex option. The exterior is characterized by the iconic octagonal bezel with eight hexagonal screws and an integrated bracelet that has been updated with a more pronounced taper and thinner links for improved ergonomics. It is equipped with a “Bleu Nuit, Nuage 50” dial featuring the “Grande Tapisserie” pattern, white gold applied hour-markers, and Royal Oak hands with luminescent coating.
The timepiece is powered by the self-winding Calibre 5900, which provides a 60-hour power reserve and operates at a frequency of 4Hz. This movement is a dedicated replacement for the previous calibre 3120, offering a thinner construction that contributes to the watch’s reduced case height. The complication is straightforward, featuring a date display at the 3 o’clock position along with center hours, minutes, and seconds. The sapphire crystal caseback reveals the movement’s finishing, and models produced specifically in 2022 feature a unique 22k gold skeletonized oscillating weight to commemorate the 50th anniversary.
General reviews of the 15550ST highlight the successful refinement of a classic design, noting that the subtle changes to the case beveling and bracelet construction significantly enhance wearability. Critics and enthusiasts alike praise the return to the original “Bleu Nuit, Nuage 50” dial color and the cleaner aesthetic achieved by removing the “Automatic” inscription. While the 37mm size is often cited as a “sweet spot” for various wrist sizes, some users note the 50-meter water resistance and lack of a screw-down crown as factors that keep it more in the realm of a luxury accessory than a heavy-duty sports instrument.