Unlike the 25657, the 25661 has a display caseback; where one can glance at the thinnest automatic perpetual calendar caliber. 🤏 #amsterdamvintagewatches #audemsrspiguet #apqp #quantiemeperpetuel #audemarspiguetquantièmeperpetuel #25661 #25661BA (bij Amsterdam Vintage Watches) https://www.instagram.com/p/Ca2F9cEtVV7/?utm_medium=tumblr













