Step drill is hexagonal handle, prevent sliping. The saw drill is a round handle.X shaped openings, drilling is not easy to slip. Higher precision, more sharp, burr-free drilling.The gold is titanium coating, more wear and oxidation , not rust.The unique step structure, a drill can drill a variety of sizes of the aperture. You can deburring, chamfering, punching elliptical hole.The hardness of the workpiece below the use of 25 below, such as iron, aluminum, PVC board, insulation board, wood, workpiece thickness 4mm.Name:Hole Cutter SetSize:Step Drill Bit:4-12mm,4-20mm,4-32mmSaw Drills:3mm,6mm,8mmMaterial:High speed steelcolour:GoldenPackage Contents:3 x Step Drill Bit3 x Saw DrillsOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.