KKmoon Portable Rectangle Anchor Adjustable Watch Screw-on Back Case Cover Opener Remover Wrench Repair Kit Tool 100% brand new and high quality Watch Screw-on Back Case Cover Opener. For opening waterproof watches case, To remove watch back case with ease in seconds. Adjustable design: Jaw distance can be adjustable from 8mm to 57mm. Very convenient and easy to take everywhere easy to use.