Strong, hardened steel screw extractors with tapered design for multiple fixing sizes. For use with all types of power drill in reverse mode. Reverse-threaded shafts enable combined bite and removal of broken screws and bolts in one action. Requires pilot hole of around 50% screw/bolt diameter. Includes sizes 1/8" - 1/4"/M3 - M6, 1/4" - 5/16"/M6 - M8, 5/16" - 7/16"/M8 - M11, 7/16" - 9/16"/M11 - M14, 9/16" - 3/4"/M14 - M18.