A men's Rolex Cosmograph Daytona model 116508bkcso. Features an 18kt yellow gold case and bracelet, black and champagne dial with yellow gold hands and indices, tachymeter function, automatic chronograph movement Calibre 4130, scratch-resistant sapphire crystal, screw-down crown for easy winding and setting, solid case back, round 40mm size, water resistant to 100 meters.