Alfa USAs Cobalt M42 Screw Machine Length drill bits are manufactured from heat resistant steel to NAS 907, Type J standards. Cobalt M42 high speed steel maintains cutting ability at temperatures exceeding 1000 degrees F. This heat resistance enables use in harder, high-tensile strength steels like stainless steel, titanium, armor plate, Inconel and other difficult-to-machine materials. Shorter flute and overall length increase rigidity resulting in less deflection, better hole accuracy and longer tool life.