Invicta Men's 4728/LTMOP Specialty Black Mother of Pearl Mechanical Chronograph Watch Mechanical-hand-wind movement; Does not require batteries Scratch Resistant Sapphire Crystal; Stainless Steel and Black Ionic Plating on Case and Band Chronograph Functions with 12 Hour, 30 Minute, 60 Second Subdials Luminous Hands; Exhibition Case Back; Black Mother of Pearl Dial Water resistant to 330 feet (100 M): suitable for snorkeling, as well as swimming, but not diving