When drilling low tensile strength materials. #49 Cobalt Long Threaded Shank Drill Bit Overall Length 2-1/8. 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 drill, resulting in a much lower cost per hole.
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 drill, resulting in a much lower cost per hole.When drilling low tensile strength materials. #29 Cobalt Stubby Threaded Shank Drill Bit Overall Length 9/16.