Back Home / Cutting Tools / Drill Bits / DRILL BIT COBALT 5/16 DRILL BIT COBALT 5/16 SKU: XTID56C Categories: Cutting Tools, Drill Bits Diameter of 5/16″. Jobber length, 4-1/2″. 135° split point. Cobalt, high speed steel Heavy duty construction. Works best in cast iron, low and medium carbon steel, high alloy steel and stainless steel. Diameter of 5/16″. Jobber length, 4-1/2″. 135° split point. Cobalt, high speed steel Heavy duty construction. Works best in cast iron, low and medium c Case Quantity: 1 Log In For Pricing