KnKut left hand hard steel drill bits are carbide tipped and made for use in drilling hardened steel in the range of 48 to 65 Rockwell "C". Holes may be drilled without annealing or appreciably changing the structure of the material. This drill bit can be used for drilling BROKEN TAPS by relieving the pressure and assisting with backing out the tap with its counter clockwise spin. When using left hand drill bits, your motor should be used in reverse mode.
NOTE: Heavy Pressure and low R.P.M.'s recommended. Cutting oil should be used. Recommended for use in drill presses, but can be used in portable drills.
Set Includes 1pc each 1/8", 3/16", 1/4", 5/16"x 4, 3/8" x 4