Master Mechanic, 5/16" x 4-1/2", Titanium Coated Drill Bit, 135 Split Point Design With 4 Cutting Edges Eliminates Walking & Permits Quick Accurate Starting, Added Lubricity Of Titanium-Nitride Surface Finish Enhances Chip Flow, Drilling Efficiency & Increases Drill Life, Recommended For Heavy Duty Drilling In Wood, Plastic, Wallboard, Plywood & Soft Metals & For Moderate Use In Heat Treated Or Ferrous Metals, Carded.