Features: 1. The head is of the special process technology, high hardness and small incision resistance 2. The surface is of painted and full grinding processing with anti-rust treatment which is smooth to drill. 3. Single threaded U-type chip discharge groove make it smoother to drill. 4. The design of triangular handle make it more fastening to clamp and not easy to slip. 5. Widely used in ceramic tile, glass, brick wall, wood, etc. 6. Can be used in the hand electric drill, table drill, etc. Specification: Condition: 100% Brand New Material: Hard Alloy Tool Holder Type: Triangle Handle Cooling Type: Outer Cold Blade Top Corner: 45° Category: Hole expansion drill Optional Style: 4-10mm(5pcs), 6-12mm(5pcs), 3-12mm(7pcs) Weight: Approx. 131-179g / 4.6-6.3oz Handle Diameter: 2.5-9mm Chip Groove Length: 40-75mm Blade Diameter: 3-12mm Blade Length: 80-120mm Package List: 5Pcs 4-10mm Drills Note: Please be sure to add water to cool when using. 1、The head is of the special process technology, high hardness and small incision resistance 2、The surface is of painted and full grinding processing with anti-rust treatment which is smooth to drill. 3、Single threaded U-type chip discharge groove make it smoother to drill. 4、The design of triangular handle make it more fastening to clamp and not easy to slip. 5、Widely used in ceramic tile, glass, brick wall, wood, etc.