Audemars Piguet Royal Oak Openworked Perpetual Calendar

・・・  The Reference 26574.1220 comes in four different versions, two in stainless steel and two in rose gold with either a navy blue or silvered “Grande Tapisserie” dial. Due to the enlarged case size (now 41mm up from 39mm), the dial and its indications are more legible. 
Dial display includes: day, date, astronomical moon, month, leap year, and now the 52 weeks of the year displayed on an outer chapter ring via an third center-mounted hand 
By @horoloupe
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