Item Type: Step Drill Bit Material: High speed steel Uses: Drilling wood, stainless steel, plastic plates, copper plates, aluminum plates Applicable Equipment: Electric drill, bench drill, battery drill, etc. Shank Type: General hex handle Size(Approx. )Step numberBlade length per step(Approx. )Shank diameter(Approx. )Total length of cutter head(Approx. ) 4 ~ 12mm / 0.2 ~ 0.5in 57mm / 0.3in6.35mm / 0.3in43mm / 1.7in 4 ~ 20mm / 0.2 ~ 0.8in 94.5mm / 0.2in6.35mm / 0.3in55mm / 2.2in 4 ~ 22mm / 0.2 ~ 0.9in 104mm / 0.2in6.35mm / 0.3in55mm / 2.2in 4 ~ 32mm / 0.2 ~ 1.3in 154mm / 0.2in6.35mm / 0.3in78mm / 3.1in Package List 1 x Step Drill Bit 1Multipurpose, can drill holes of different diameters, simple and convenient operation 2Accurate drilling, the product can be rounded, reamed, and deburred, suitable for hand drills, bench drills and battery drills, etc. 3With Xshaped opening design, it can effectively reduce drill bit slippage and easy to operate 4The product has a scale, the diameter can be seen intuitively, and the marking is clear 5The step drill bit is suitable for drilling wood, stainless steel, plastic plates, copper plates and aluminum plates