Description: HSS Step Cone Plating Drill Bit Hole Cutter, is made from high quality HSS steel with coated to reduce friction and heat, which is used to cut thin iron plate, aluminum material, insulation plate, PVC plate and more. Unique step structure make it possible to open various size of holes. Features: 1. Made of high speed steel, hard, wearproof and . 2. Handle with coated, reducing friction and heat. 3. Unique step structure make it possible to open various size of holes. 4. Compared with ordinary drill, not easy to break. 5. Ideal for cutting holes in a variety of materials including steel, bronze, aluminum and more. Specifications: Material: HSS4241 Surface Treatment: Plating Handle Shape: Hex Color: Yellow Bit Type: 4-32mm, 4-20mm, 4-12mm, 3-12mm(Optional) Package Includes: 1 x Step Drill Bit