18k Yellow Gold, black rubber Oysterflex with flip-lock Oysterclasp and Easylink extension link, engraved tachymetric scale bezel, black / gold dial, automatic Chronometer (Cal. 4131), 12-hour chronograph, screw-down crown and pushers, Ref. 126518LN-0004, warranty dated July 2024, 40mm, Like New in Box with Papers