IRWIN 63120 Jobber Drill Bit, 5/16 in Dia, 4-1/2 in OAL, Spiral Flute, 5/16 in Dia Shank, Cylinder Shank

High-speed steel with M-35, 5% cobalt, for higher heat and abrasion resistance; heavy-duty web construction for strength and durability. Split point begins drilling immediately, minimizing bit walk when used in applications such as metal drilling, including heavy-duty abrasive alloy metal drilling on hardened steel (heat-treated).