Features: The step drill bit is made from high speed steel of high hardness and good wear resistance. Surface is coated with titanium which give the drill bit a beautiful gold color and will not fade easily. This single drill bit can be used for drilling a wide range of hole sizes from 3mm to 13mm. It is most commonly used on softer materials such as thin iron sheet, aluminum, PVC and wood board of 5mm or smaller. Step drill is great for use in work where thin steel, aluminum or plastic boxes and chassis are encountered. Specifications: Material: High speed steel 4241 Surface Finishing: Titanium coating Step Size: 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm Hex Shank: 1/4" Quantity: 1pc Package Includes: 1 x Step Drill Bit