Drill America DWDLH series polished jobber length drill bit. General purpose drill construction. Features a left hand helix for screw machine applications where spindles rotate counter-clockwise. Left hand drill can also be used to drill out broken bolts. 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. Reverse-flute drill bits run in the opposite (clockwise) direction from regular drill bits when making holes.