Patek Philippe Aquanaut Selfwinding Chronograph - 42.2 mm Steel Case - Black Dial - Orange Composite Strap - 5968A-00142. 2 mm steel case, 11. 9 mm thick, sapphire crystal back, black embossed dial, gold applied numerals with luminescent coating, caliber CH 28 520 C 528 self winding movement with flyback chronograph, central chronograph hand, 60 minute counter, date in an aperture, approximately 45 55 hours of power reserve, black composite material strap (orange also included), Aquanaut fold over buckle. Water resistant to 120 m. 2021 Papers.