The A170 drill comes in a range of fractional and metric diameters. However, regardless of the cutting diameter, all A170 drills come with a ? inch parallel shank. This means drills with a large cutting diameter can still be clamped in conventional, hand held power tools. The A170 is manufactured from premium High Speed steel making it suitable for drilling many materials, including steels, stainless steels and aluminium and comes with a conventional 118 degree point, providing strength and making regrinding easy. It has a steam oxide finish to stop work piece material from sticking to the cutting edge of the tool. The A170 ? inch parallel shank drill can be used in many different hand held and machine applications.