Features: HSS-Co/M35:More than 4241and 6542 high-speed steel materials.118° X Bit Design, you can drill from any angle, no slipping. Double-edged 1/4Inch hexagon shank, protection cone design, super torque New design, great chip removal, small resistance, geat heat dissipation.Higher accuracy sharper achieve drilling burr. Plated cobalt coating, a substantial increase in the wear resistance and oxidation resistance. Ideal for cutting through metal, wood and plastic quickly and easily Suitable for Aluminum, insulation board, PVC board chamfer, steel, aluminum, sheet metal, carbon steel, 304 stainless steel, etc. Specifications: Item: M35 Cobalt Step Drill Bit 3-13mm Material: M35 Cobalt(HSS-Co) Shank: 1/4 Inch Hexagon Shank for: CNC-CBN grinding wheel. Size:11 Steps:3,4,5,6,7,8,9,10,11,12,13mm Length：approx 7.7cm/3.03in Shank Diameter:approx 6.35mm/0.13in Package Includes: 1 x Step Drill Bit note: 1. Due to manual measurement, please allow 1-3cm error. Make sure you do not mind before bidding. 2. Due to the difference of different monitors, the picture may not reflect the actual color of the product. Thanks.