Product Description5PCS Step Drill BitStep Drill BitMaterialSteel High Speed, Titanium Brass, High Speed Steel, Alloy Steel Brass, High Speed Steel, Alloy Steel,Titanium Brass, High Speed Steel, Alloy SteelColorSilverDrill ShapeStep Drill Bit Size5mm-35mmFlintronic 5-35mm Large Size Titanium Coated Trephine Bur, HSS, Spiral1.If you need a storied forest very satisfied, stop, this is what you need.2. is used made of HSS high speed steel, the titanium alloy liner, durable.3.It is very suitable for to use to punch holes in a variety of of materials such as steel, brass, wood, plastic, thin iron plate, aluminum material, insulation plate, PVC plate, etc.Widely used; and concerned:Compatible models, bench drill, bench drill; hand, rechargeable drill.Tapered is suitable for drilling larger and deeper holes, or for the widening of the opening in the zones where he was drilled.Cutting blade design enables faster cutting, automatic deburring of the hole when drilling.Advantages: 1. Use twist drill : pre-drilling by drilling step by step not, reduce the damage to the workpiece during drilling. 2. CNC machine tools, each process is strictly controlled; and each step of quality control. 3. Compare to the twist drill, the stepped drill; is not easy to break and can cut different size holes. two flutes: The capacity chip removal is better and the drilling speed is accelerated. Improve your productivity.Attractive design and practical home improvement and general building monitoring / technology.Long life The punch of centering is made of alloy steel. impact resistant for easy positioning before drilling and breaking glass. Positioning and pre-drilling to protect the conical drill bit.