For convenience and value, check out this expansive set of 230 premium titanium-nitride coated high speed steel drill bits. (High speed steel is often used in cutting tools like drill bits and saw blades; it retains its hardness at high heats, making it possible to cut faster). Twenty-seven sizes ranging from 3/64" to ½", in multiples of 5 to 10 of each size. Comes in a steel storage case. And when you need that extra reach, our 12" long Aircraft Drill Bits can’t be beat. A set of ten, in sizes ranging from 3/8" all the way down to a tiny 1/16".