Convenience Staged drilling allows you to cut multiple hole holes with one drill bit, without constantly changing drill bit. Two-Flute Spiral Groove Design Allows faster, more stable and smoother cutting. It can automatically chamfer the hole to clean the drill bit. HSS and coated titanium Made of super strong HSS steel and coated with titanium, the titanium coating ensures easy cutting steel, aluminum sheet, brass, copper, plastic, wood etc. Hex Shank 6.35mm hex shank works with most drill bits or drills with a 6.35mm (1/4 "") chuck, fits power tools perfectly and eliminates slippage. Application Suitable for sheet metal, sink, car repair, etc. Widely used for cutting holes in a variety of material like plate, aluminum, insulation board, PVC board, wood thickness within 5mm. Usage: Aplly in gun drilling, bench drill Material: HSS steel Finish: titanium Type: Step Drill Head Type: Hexagon Shank Quantity: 3PCS Material: High speed steel Surface treatment: Titanium coated Color: as the picture show