Cleveland 29 piece high speed steel general purpose screw machine length drill bit set. High-speed steel tools are good for most general purpose applications, offering a combination of hardness and toughness for wear resistance. Uncoated tools feature just the base substrate without any additional treatment or coatings and are suitable for a wide range of applications. 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. Set size range: 1/16-inches - 1/2-inches. 1/64-inches set size increment. Huot metal index set case type. 2120 drill style.