Irwin Tools 1899897 Impact Performance Series Hex Shank to Square Drive Socket Adapter, 1/4-Inch Hex to 1/2-Inch Square, 3-Inch Length, 1-Piece Built for maximum durability and long life with impact drivers Ball retention design for quick-change applications Forged socket body for additional strength Black oxide finish resists corrosion and increases life of bit 1/4" quick-change shank is designed to work with impact drivers, and reduces slipping in standard drill chucks