Irwin Impact Performance Series BOLT-GRIP Extractors, No. 1859143, feature reverse spiral flutes engineered to provide maximum gripping power to easily remove the most stubborn of broken, damaged or rusted nuts, bolts and screws. While they're built for maximum durability and long life with impact tools, they also work perfectly with rotary drills and drivers. They are manufactured with high carbon steel, ensuring longer life and greater durability, and the universal lobular design fits all types of fasteners.