IRWIN POWER-GRIP SCREW AND BOLT EXTRACTOR SET 7 PIECEThe IRWIN Tools 394100 Power-Grip 7-Piece Bit Set is a durable collection that works with many power tools including cordless drills, impact drivers, and nut runners | The power grip set helps remove rounded off, painted over, damaged, and rusted over nuts and bolts | The bit set also features a black oxide finish with white markings which prevents rust and easy-to-read markings | Additionally, the bits themselves have reverse spiral flutes which are designed to bite down, and are also made of shear-resistant, high-carbon, steel shank | Other features include a 1/4-inch hex shank, universal lobular design to fit all types of fasteners, and maximum gripping power on both metric and SAE