Please Note : Due to some customer don;t know how to connect the rubber strap with buckle ; So right now we update new structure strap and Hook buckle 1-Japan miyota 8215 Automatic Movt 2-Stainless Steel Case 3-Rubber Strap 4-40MM diameter without crown 5-screw crown 6-waterproof 7- Stainless Steel Case Caseback Real Show Real show open Steel Caseback Japan Miyota 8215 Automatic Movement Band width: 21.0 millimeters Case diameter: 42.0 millimeters Item shape: Round Case thickness: 11.0 millimeters Clasp type: Hook buckle