Get the right fastening accessory for your impact driver: the Makita® 3 Pc. Magnetic Nutsetter Set (1/4", 5/16”, 3/8”) is ideal for driving hex head nuts and self-tapping screws in a wide variety of applications. These hex shanks are for use with high-torque impact drivers and driver-drills. Flat edges at the hex opening provides full contact with flanged hex head screws.