Viking Type 240-D Premium Cobalt HSS Drill Bits are manufactured from M42 high speed steel containing 8% cobalt which increases high red hardness of the tool steel, making cobalt bits ideal for drilling work hardening grades of Stainless Steel, Titanium and other Nickel based alloys, hard and tough metals and certain abrasive plastics. Viking Type 240-D Cobalt bits feature a 135° Split Point for fast penetration and easy starting without the use of a center punch or pilot bit. Gold surface treatment provides additional lubricity, reduces wear and assists swarf in traveling along the flutes during drilling. Bits are of one piece solid construction, and are manufactured in the USA to NAS 907J specifications of special M42 8% Cobalt high speed tool steel. Cobalt bits are more brittle than standard steel bits and should be used with rigidly held positive feed drilling equipment to avoid snapping.