Made from rugged S2M tool Steel100% made in the U.S.A.Custom heat treated for strength and durabilityManufactured to tight tolerances to ensure accurate fit1/4" hex bodyFits all standard multi-bit screwdrivers and power drillsIDEAL Combo Head Bits are made from custom heat-treated S2M tool steel for strength and durability. These bits fit all standard multi-bit screwdrivers and power drills! They are equipped with a power-locking groove which are manufactured to tight tolerances for accurate fit, and their patented tips ensure for full fastener engagement.