5/16", Turbo Max, Jobber Length Drill Bit, Self-Centering, Precision Ground Turbo Max Feature 135 Degree Point Tip Eliminates Walking On Flat & Curved Surfaces, Stays Sharp Longer, 3 Flatted Shank On 3/16" For Exceptional Grip On Chuck, Manufactured With Premium High Speed Steel With Black & Gold Oxide Coating For Maximum Corrosion Existence.