You can use water to cooling it when it is work and it can be used for even longer HSS-6542 Black Oxide Tapping Tool M4x0.7 Spiral Point Tap And Drill Bit Set Titanium Uxcell M4 X 0.7 Spiral Point Thread Tap & 3.3mm Drill Bit Set - Titanium Plated Cobalt HSS Hss6542 M2 Stee Spiral Groove Step Drill Bit 4-20mm 1 Driak 3 Pics HSS6542 M2 Steel Spiral Groove Unibit Rwanda Cone Drill Bit Suit for use in hardness under 28 artifacts,(Such as: Stainless steel , iron plate, aluminum, wood ); You can use water to cooling it when it is work and it... Suit for use in hardness under 28 artifacts,(Such as: Stainless steel , iron plate, aluminum, wood ) Find many great new & used options and get the best deals for Set of 3 Hss6542 M2 Steel Spiral Groove Step Drill Bit for Stainless Metal at the best online prices at Compared with the ordinary twist drill,it is not easy to break and it can be used for deburring, chamfering and open hole Recommend the drilling speed of 250--400 rpm Specifications: Material:HSS6542 Shank Type:Triangle shank Type:Spiral groove
