IRWIN Impact Performance Series Quick-Change Extensions are for peak durability and womb-to-tomb life with impact drivers. The quick-release guarantees immediate bit changes and the proprietary jaw design is harmonious with all 1/4 '' hex shank accessories, including insert bits. These extensions a elephantine chuck that withstands the overlooking torque of impact drivers and the fatal oxide finish resists corrosion and increases life of the extension. Plus, the 1/4 '' changeable shank with impact drivers and reduces slipping in accepted drill chucks.