Audemars Piguet Selfwinding Blue Sapphire "50th Anniversary"

The Audemars Piguet Royal Oak Selfwinding Blue Sapphire "50th Anniversary", reference 15554BC.SS.1274BC.01, has a case measuring 37 mm in white gold. The case stands 9.8 mm thick and holds a sapphire crystal over a blue dial. Inside is the self-winding calibre 5909, which drives hours, minutes and a central seconds display. The watch is set with diamonds and comes on a white gold bracelet fitted with an AP folding clasp. It belongs to a set of ten Royal Oak references, each finished with a different gemstone for the collection's fiftieth anniversary. Water resistance is a modest 20 metres, more suited to occasional wear than daily exposure.