IRWIN Impact Performance Series Quick-Change Adapters are engineered for maximum durability and long life with impact drivers. They adapt a standard square chuck to a 1/4" hex chuck so they're compatible with all impact drilling accessories. The quick-release system guarantees fast bit changes, and the patented jaw design is compatible with all 1/4" hex shank accessories, including insert bits. These adapters have a large chuck that easily withstands the higher torque demand of impact drivers. Plus, a black oxide finish resists corrosion and increases the life of the extension.