Description While most screwdriving bits are simply compatible with impact drills and drivers, IRWIN; Impact Performance Series(tm) fastener drive bits are engineered for maximum durability and long life with impact drivers These bits are forged* rather than milled, so they fit fasteners more precisely, which reduces stripping and increases the life of the bit itself ? IRWIN's Impact Performance Series bits have three times longer life than traditional bits Manufactured with heavy-duty, cold-forged, high-grade steel, they'll withstand extremely high torque output Plus, a black oxide finish resists corrosion and increases the life of the bit. Built for maximum durability and long life with impact drivers Forged bit (vs. milled) for superior fitment, which reduces stripping and increases life of bit 3X Manufactured with heavy-duty, cold-forged, high-grade steel to withstand high torque output. Black oxide finish resists corrosion and increases life of bit.