M35 Cobalt Four Spiral Flute Step Drill Bits 1/4”-3/4\"(9 Step Size) Impact Unibit Step Drill Bit 1/4\" Hex Shank Step Bits for Metal Aluminum Wood Plastic

M35 Cobalt HSS Step Drill Four Spiral Flute Cobalt Step Drill Bit 1/4”-3/4\"(9 Step Size) Impact Unibit Bit M35 cobalt high speed steel can be obtained by proper heat treatment with high hardness high red hardness and high wear resistance. The service life is twice that of ordinary ladder drills the drilling accuracy is significantly improved the cutting speed is faster when drilling. TiAlN coating is a new coating material in recent two years. It has high hardness high oxidation temperature good thermal hardness If you are not fully satisfied for any reason please contact us We will provide you with Worry-free after-sales service.