Audemars Piguet Royal Oak Series, Complicated Function Perpetual Calendar Watch Model: 26574ST.OO.1220ST.01 Noble Timepieces The Audemars Piguet Royal Oak Series Perpetual Calendar Watch features a sophisticated and elegant blue dial paired with a striking stainless steel case, perfectly embodying Audemars Piguet's aesthetic design and highly technical complexity. The case is made from 316L stainless steel, with a diameter of 41mm and a thickness of 11.4mm. The blue dial is adorned with a Grande Tapisserie pattern, featuring a classic design with three-dimensional hour markers and faceted hands coated with luminescent material. Three sub-dials displaying calendar functions and a moon phase indicator are symmetrically arranged on the dial, orderly presenting the hours, minutes, day, date, week, month, and moon phase. All functions on the dial are easily accessible. The mineral crystal glass is treated with anti-reflective coating, enhancing the watch's overall clarity and brightness. This remarkable timepiece is identified by the reference number Ref. 26574ST.OO.1220ST.01.