Black and gold surface treated 1/4" quick change hex shank Single bit can be used for drilling a wide range of hole sizes in metal, plastic and wood Exlusive single radial concave flute crates perfectly round holes in metal, plastic wood and other thin materials without center punching Contructed of industrial grade high-speed molybdenum steel, heat-treated and temperature for long life No center punching needed Automatically deburrs top side of hole. Ideal for steel, copper, aluminum and other thin materials