Incorporating the Patek Philippe 324 S QA LU 24H movement, the new Ref. 5726 is the first Nautilus model with an Annual Calendar. It comes in a stainless steel case and is worn on an alligator strap. Its black dial, sleek and casually elegant, is designed for optimized legibility . GENERAL * Mechanical self-winding movement * Caliber 324 S QA LU 24 H * Annual Calendar * Day, date, month in apertures * Moon phases and am/pm indicator * Sweep seconds hand * Black dial, gold applied hour markers with luminescent coating * Strap: alligator with rectangular scales, hand-stitched, matt black * Nautilus fold-over clasp * Screw-down crown * Sapphire-crystal case back * Water resistant to 120 m * Steel * Case diameter (10-4 o'clock): 40.50 mm