Features: Great for opening and closing screw back case, especially for Rolex oyster model. Including a wrench and six grooved dies of different diameters. Adopting premium steel material with stable construction, it is rustless and durable. Easy and handy to take with you because its small size and light weight. It comes with a storage box for easy storage and well organization. Specification: Material: SteelColor: Silver Item Model: 5537Wrench Size: 20 * 1.6cm / 7.87 * 0.63inch Diameter of Dies: Approx. 18.50mm / 0.73inch20.20mm / 0.8inch22.50mm / 0.89inch26.50mm / 1inch28.30mm / 1.11inch29.50mm / 1.16inchWeight: 367gType: Watch RepairTools& KitsPackage List:1 x Wrench6 x Dies.Note:Before buying, measure the size of the back cover of your watch to see if it matches the six molds 18.50mm, 20.20mm, 22.50mm, 26.50mm, 28.30mm, 29.50mm, and the size is the same before you can buy.