Patek Philippe Aquanaut Chronograph Black Dial Self-winding mechanical movement. Caliber CH 28_520 C. Black embossed, gold applied numerals with luminescent coating. Steel. Screw-down crown. Sapphire-crystal case back. Water-resistant up to 120 meters. Diameter (10-4 oÕclock): 42.2 mm. Height: 11.9 mm. Composite material, black (originally fitted). Composite material, orange (additional strap). Aquanaut fold-over clasp