The Mayhew Tools 10-pc Screw Extractor Set is made of hardened steel with fluted edges for easy removal of broken screws, bolts, studs and pipes. The heavy duty storage case has available space to store drill bits along with the extractors. A detailed diagram is included to indicate use. This set covers bolt range from 1/4" to 1-1/2". This set is made in the U.S.A.