Stone Tool's 21 piece jobber cobalt drill bit set is constructed of industrial quality cobalt steel and vacuum treated to achieve hardness of HRc 66-68. Add this drill bit set to your HomElectrical.com cart today!
- 21 Piece Set: 1/16-in to 3/8-in by the 64ths.
- Industrial Quality COBALT Steel makes these drill bits more durable and stronger than the Black & Gold Jobber bits.
- Precision grounded from solid for true, round holes when cutting.
- Vacuum heat-treated to achieve hardness of HRc 66-68.
- 135 degree Split Point prevents and reduces wobbling and walking.