Housed in a 37mm stainless steel case, this Royal Oak carries a bezel set with 40 brilliant-cut diamonds totalling approximately 0.92 carats, lending a refined presence to the watch's distinctive octagonal silhouette. The case is water resistant to 50 metres and secured to a stainless steel bracelet fastened by an AP folding clasp.
The dial is rendered in "Bleu nuit nuage 50", a deep nocturnal blue worked with the "Grande Tapisserie" textured pattern that has long defined the Royal Oak family. White gold applied hour-markers and Royal Oak hands with luminescent coating complete the dial, ensuring legibility across varied lighting conditions. Functions include hours, minutes, centre seconds, and date.
Powering the watch is a selfwinding movement measuring 26.2mm in diameter and 3.9mm thick, comprising 188 parts and 29 jewels. It beats at 4 Hz — 28,800 vibrations per hour — and offers a power reserve of approximately 60 hours. Reference 15551ST.ZZ.1356ST.05 is listed under model Royal Oak by Audemars Piguet.
