Watch Pavilion Professional Watch Case Back Opener for Waterproof Watches with Yellow Storage Box Holder Change Battery Adjustments Remove Open Caseback Watch case opener will open most waterproof watch cases. Change batteries quickly. Includes four sets of different type of chucks. Must have tool for any collector. Made of high quality steel to help form a tight grip when removing the metal caseback Easy to use and adjustable for different sized watches. Tool comes in a yellow storage box to hold all pieces. Original design by Watch Pavilion.