Audemars Piguet Royal Oak Perpetual Calendar 25654ST, ‘90s Stainless steel octagonal case, n.D-60437 - N°1091, octagonal steel bezel. Grey dial, applied indexes, indication of the date, day of the week, month, phases and age of the moon (last-series dial with tall AP logo). Automatic movement, cal. 2120/2800, n.374299. Stainless steel integrated bracelet with deployant buckle. Size: 39 mm. Accompanied by Audemars Piguet winding box and warranty. Notes: Reference 25654 is the most iconic Royal Oak perpetual calendar model; only 272 pieces were produced in stainless steel, 422 pieces in yellow gold, 72 in two-tone, 33 in platinum, and one in white gold.