Universal Drilling Tool Set, 3-8mm 5pcs Efficient Drill Bit Set, Anti-Rust Alloys and All Polished Drill Bits, Stable Drilling and Edgeless Breaking, Drilling Tools for Tiles, Marbles, Cast Iron Plate, Mirrors, GlassFeatures: High-quality Materials: High-quality alloys are used as raw materials. Bit oxynitride technology increases the hardness of the bit. Surface electrophoresis painting process: all polished and anti-corrosion, clean and tidy without burrs. The drill bit is more wear-resistant and more durable. Fully automatic polishing: CNC polishing is fully automatic, and each piece is uniform. Unique angle design: low cutting resistance, stable drilling, fast and edgeless. The hole is neat, smooth, no broken edges, no shaking, and not easy to break. Widely Used: Professional glass and tile drill bits can perform smooth and accurate drilling on tile, marble, thin iron, mirrors and glass. Be sure to add water or coolant when drilling.5 different sizes: suitable for different needs. It can be installed on general hand drills and bench drills. The range of the machine drilling machine is 10mm and above. Specification:Size: 3+4+5+6+8mm/0.12+0.16+0.2+0.24+0.31inchMaterial: AlloyWeight: 110grams(5pcs)Note:Due to the different monitor and light effect, the actual color of the item may be slightly different from the color showed on the pictures. Please allow 1-2cm measuring deviation due to manual measurement.5 x Drill Bits