1、Multi‑purpose, can drill holes of different diameters, simple and convenient operation 2、Accurate drilling, the product can be rounded, reamed, and deburred, suitable for hand drills, bench drills and battery drills, etc. 3、With X‑shaped opening design, it can effectively reduce drill bit slippage and easy to operate 4、The product has a scale, the diameter can be seen intuitively, and the marking is clear 5、The step drill bit is suitable for drilling wood, stainless steel, plastic plates, copper plates and aluminum plates 1 x Step Drill Bit Item Type: Step Drill BitMaterial: High speed steelUses: Drilling wood, stainless steel, plastic plates, copper plates, aluminum platesApplicable Equipment: Electric drill, bench drill, battery drill, etc.Shank Type: General hex handle Size(Approx. ) Step number Blade length per step(Approx. ) Shank diameter(Approx. ) Total length of cutter head(Approx. ) 4 ~ 12mm / 0.2 ~ 0.5in  5 7mm / 0.3in 6.35mm / 0.3in 43mm / 1.7in 4 ~ 20mm / 0.2 ~ 0.8in  9 4.5mm / 0.2in 6.35mm / 0.3in 55mm / 2.2in 4 ~ 22mm / 0.2 ~ 0.9in  10 4mm / 0.2in 6.35mm / 0.3in 55mm / 2.2in 4 ~ 32mm / 0.2 ~ 1.3in  15 4mm / 0.2in 6.35mm / 0.3in 78mm / 3.1in