Threaded Shank Drills, Fractional
- Threaded shank drill bits are type D adapter style
- They are made from M42 8% cobalt and are manufactured to NAS 965 Type "D" specifications
- They have 135º heavy duty split point and surface treated for drilling hard, tough, high tensile strength materials
- When drilling low tensile strength materials, the Type "D" cobalt drill will have a significantly greater tool life than the NAS 965 Type B high speed steel adapter drills resulting in a much lower cost per hole.