MOVEMENT: Japanese OS 20 Working Chronograph Quartz Movement CASE DIAMETER:�43.5mm� THICKNESS:�11.5mm� DIAL COLOR: White Dial with Black Subdials, Roman Markers CASE MATERIAL:�Solid�Stainless Steel 316 BRACELET:�Leather Strap with Insignia Single Fold Deployant Buckle FRONT GLASS:�Sapphire�Crystal BACK GLASS: Solid Case Back with Insignia Engraving HACK MOVEMENT:�Yes