Drill America - Dwdrsd59/64 59/64" Reduced Shank High Speed Steel, Dwdrsd Series Made of HS Steel and ground to a 118 point. These drills expand the size range capacity of a portable drill chuck. Common flute and overall length for minimal adjustment during tool changes. Precision ground for high degree of concentricity between shank and body diameter. Ideal for drilling in low and medium tensile strength materials. Black oxide finish. High-speed steel tools are good for most general purpose applications, offering a combination of hardness and toughness for wear resistance Black oxide treatment adds lubricity and creates small pockets on the surface of the tool that act to hold coolant near the cutting edge Round shanks allow use with a wide variety of toolholding systems When run in a counterclockwise direction (right-hand cut) spiral fluted tools evacuate chips up and out of the cut to reduce clogging Ideal for drilling in low and medium tensile strength materials