description of goods: HSS Step Cone Titanium Plating Drill Bit Hole Cutter, is made from high quality HSS steel with titanium coated to reduce friction and heat, which is used to cut thin iron plate, aluminum material, insulation plate and PVC plate. Unique step structure make it possible to open various size of holes. Feature: 1. Made of high speed steel, hard, wearproof and durable. 2. Handle with titanium coated, reducing friction and heat. 3. Unique step structure make it possible to open various size of holes. 4. Compared with ordinary twist drill, not easy to break. 5. Ideal for cutting holes in a variety of materials including steel, bronze, aluminum and more. Spezifikations: Material: HSS4241 Surface Treatment: Titanium Plating Handle Shape: Hex Bit Type: 4-12mm, 4-20mm, 4-32mm Weight: Approx. 244g Package Includes: 3 x Step Drill Bit 1 x Storage Bag