Audemars Piguet Royal Oak 15400ST Black Dial 41MM 15400ST. Audemars Piguet 15400 Royal Oak 15400ST. Please allow 1-2 day processing. Our family business always strives to treat customers like family. Established in 1993 and located in the heart of Boston’s Back Bay, we stock a curated selection of new, pre-owned, and vintage wristwatches. Designed & Developed By. Designed & Developed By : eFusionWorld.