Carbides are extremely hard materials that can drill in virtually all workpiece materials while holding an edge longer than other bits.High Speed Steel (HSS) is a form of tool steel where the bits are much more resistant to the effect of heat. They can be used to drill in metal, hardwood, and most other materials at greater cutting speeds than carbon steel bits and have largely replaced them in commercial applications. Solid Carbide and HSS Drills feature special geometry and other enhancements that provide greater hole dimensional accuracy at higher production rates.