3-12 mm 4-20 mm High-Speed Steel Coated Step Drill Bit High Speed Steel Metal Wood Hole Cutter Cone Drilling Tool

Works great in making a smooth, clean and perfectly round hole 3 Sets Step Drill: With 3 sets 5 stage + 9 stage + 15 stage step drill, you can drill different sizes from small holes to big holes Two-fluted design provides faster, smoother cutting;Provided with small pressure and the sets can cut through wood, sheet metal, steel and other surfaces Ideal for using to cut holes in a variety of materials including steel, brass, wood, plastic, etc HSS steel large step cone drill titanium bit set hole cutter, which is made from high quality HSS steel, and with the Titanium coated to reduce friction and heat 【Widely Used】Perfect Step Drill Bits suitable for drill holes in various material: within 3mm/0.12 inch (Iron Plate, Copper Plate, Aluminum Plate); within 5mm/0.2 inch (Wood, PVC sheet, Insulation Boards). Not suitable for hard and brittle materials such as stainless steel, glass, tile floors, walls etc. 【Material】HSS combined with a titanium coating. More capable and Sturdy. 【Easy Drilling】Two-Flute Design for smoother cutting. High Step design let you feel the stop and never drill bigger in mistake