Features 1. This manual case opener is designed specifically for opening the back cover of a watch case. 2. The unique way of opening the shell makes it impossible to use a regular shell opener and requires the use of such specialized tools. 3. Screw housing for opening and installing Rolexs and Tudor watches. Including a wrench and six groove inserts. 4. Six slotted clamps with diameters (in millimeters) of 18.5 millimeters, 20.2 millimeters, 22.5 millimeters, 26.5 millimeters, 28.3 millimeters, and 29.5 millimeters, respectively. NO.0-18.50 millimeters (0.73 inches) NO.1-20.20 millimeters (0.8 inches) NO.2-22.50mm (0.89 inches) NO.3-26.50mm (1 inch) NO.4-28.30mm (1.11 inches) NO.5-29.50mm (1.16 inches) Specifications: Tool type: Repair kit Material: Steel Diameter: 18.5 millimeters, 20.2 millimeters, 22.5 millimeters, 26.5 millimeters, 28.3 millimeters, 29.5 millimeters Quantity: 7 pieces Package Include: 1 x screwdriver 6 x slotted sleeves