This Milwaukee Tool 48-32-4135 Shockwave Impact Torx T20 Insert Bits is a reliable and efficient power tool for your fastening needs. It features a 1-inch drive size and a hex shank size of 1/4 inch, The bit style is Torx(R) and the finish is black phosphate. The tool is made of steel and has a weight of 0.2900 pounds. It is impact rated and has a single end/double end single end design.