High-quality materials: Our step drill is made of high speed steel, enabling fast, comfortable and friction-free drilling; a small case for easy storage and carrying. Titanium coated: The step drill with titanium coating provides good resistance to corrosion, heat and rust; reduces friction and heat; for longer service life even in extreme temperatures. 13 drill sizes: You only need one step drill for different hole sizes; The step drill has 13 sizes: 5mm, 7mm, 10mm, 12mm, 15mm, 17mm, 20mm, 22mm, 25mm, 27mm, 30mm, 32mm, 35mm. Fast drilling: The double blade design ensures faster, smoother cutting. Please note that when the step drill is running, please add water to cool down the step drill. The service life of the HSS step drill is effectively extended. Material: The step drill is suitable for household repairs and light work such as drilling holes in plastic, copper, aluminum and many other types of sheet metal; but not suitable for stainless steel. Features: HSS step drill made of