Niversal Size: The package includes 3 pieces of magnetized screw rings. Each bit magnet ring measures approximately 0.87 inches (22 mm) in length with an inner diameter of 1/4 inch (6.35 mm). Suitable for 1/4 inch hex shank screwdriver bits and power bits, compatible with hex, torx, hex screwdriver, and power bits Simple to use: The screw ring securely holds bits in place to prevent slipping. With a magnet, it catches screws quickly and firmly. It works well for fixing and mounting screws, reducing abrasion to both the screw and the screwdriver, and improving your work efficiency Wide Usage: This magnetic screwdriver ring can be used in various applications, helping you tackle many work tasks. It's ideal for auto repair, furniture assembly, accessory fixing, and other various installations. This handy tool makes your life easier