The Royal Oak Perpetual Calendar watch from Audemars Piguet. 18K yellow gold case with an octagonal bezel and smooth lugs made of the same precious metal. 8 catchy screws on the bezel, one on each vertice of the octagonal design. Skeleton dial with luminescent hands, luminescent index hour markers, perpetual calendar display subdials at 12, 3, and 9 o'clock and moon phase display subdial at 6 o'clock. AP 2120/2802 caliber self winding movement with 40 hours power reserve. 18K yellow gold strap with push-button folding clasp.