Spiral HSS Step Drill Bits Set, Titanium Coating High Speed Steel, 3pcs Black 4 12mm/3 12mm/4 20mm Hex Shank Design Drilling Tools for Plastic, wood, soft metal

【High QualIty Materials】M35 cobalt-containing step drill (HSS Co) is a high-hardness step drill, mainly used for drilling high-hardness steel plates, such as stainless steel plates, quenched steel plates, etc,the thickness within 5mm, to meet the work that cannot complete with ordinary HSS4241 step drills. 【Cobalt Drill Bit】The addition of cobalt increases heat resistance. No need for center punch, not easy to break, can be used for deburring, chamfering and opening. It is widely used in metal manufacturing because of its ability to resist wear over conventional high speed steels. this step drill also performs well in corrosion and rust resistance. 【Spiral Flutes and Hex Shank Design】Spiral Groove: Enables a faster, more stable and smoother. two-flute design clears chips faster and allows particles to escape easily. 6.35mm Hex Shank fits into power tools chuck securely and eliminates slip. 【Wide Application】Perfect Step Drill Bits suitable for drill holes in various material. Drill and Enlarge Holes in Stainless Steel Iron Hard Metal Sheet, plastic, aluminum, copper, iron sheet and many other types of sheet metal. 【Service Guarantee】 Customer satisfaction is our greatest motivation, we will do our best service, if you have any questions about this step drill bit, please feel free to contact.