Features Smooth Cutting: 4 cutting blades designed with four spiral grooves ensure faster and smoother cutting, bring you efficient use results. High Hardness: With a surface hardness of 89HRC, the drill bit set can cut harder materials and achieve higher cutting speeds, reliable and practical. Precise Steps: With 14 steps, this stepped drill provides precise hole sizes in incremental increments, allowing for accurate and controlled drilling. Wide Application: M35 cobalt high speed step drill ideal for cutting stainless steel, metal sheets, wood, plastic, aluminum sheets, copper, and other metal plates. Durable Construction: The use of 8% cobalt in the drill bit enhances its hardness and heat resistance, ensuring long lasting durability. Specification:Item Type: Step DrillMaterial: M35+CobaltPunching Diameter: 4 6 8 10 12 14 16 18 20 22 24 26 28 30mmHandle Diameter: 1/4 inch Package List:1 x Step Drill 1 x Storage Box Package List 1 x Step Drill 1 x Storage Box