The HSS Countersink Bit, Cylindrical Shank performs smooth countersinking for screws and deburring of holes in soft materials. The ground countersink is made of HSS (high-speed steel) that offers an optimum surface quality for even work in pliable surfaces. Excellent results in soft materials are made possible by five 90-degree cutting edges that continuously work free of chattering and without leaving burrs. It is suitable for use on wood, plastics and non-ferrous metals and has a cylindrical shank system. Cylindrical shank compatible with three-jaw drill chucks. Features and Benefits • Smooth Countersinking in Soft Materials Specifications Diameter: 8,0mm Step height: M 4 Total length: 48mm Shank diameter: 1/4inch Shank diameter mm: 8