1Prevent Slipping: Watch back opener with 7 different grooved chucks, can fit your watch perfectly, allow you can rotate easily without slipping. 2Usage: Watch cover opener is great for opening and closing waterproof and grooved watch cases, also convenient for changing the watch battery. 3Suitable People: Watch back opener is suitable for watch maintenance personnel, watch repairmen, and amateurs who like DIY watch repairing. 4Easy Operation: Watch case opener is an essential tool for watchmakers and watch repairers, easy to operate, allow you can repair your watch by yourself. 5Stainless Steel: Watch back cover opener adopts high quality stainless steel material, effectively resists oxidation and rust, which can repair your watch without damaging it.