Feature:1. [High Quality Material] The drill bit is made of high quality YG6X alloy as material, the oxygen ignition process of the bit enhances the hardness of the drill bit, which is easy to break the drilling object.2. [No Rust] The cover of the cement drill bit is electro gloss painted with a full polishing and anti rust treatment, without burrs. and glazing opening, no broken edge, no shaking condition .3. [Fully Automatic Polishing] The hole opener bits are CNC fully automatic polished, each one is uniform, the bits are more and durable. Remember to add water or coolant when drilling.4. [Cross Angle Design] The home electric drill bit adopts a unique angle design, with low resistance to cutting, stable drilling, fast speed, and no cutting edge, which enhances the experience of using.5. [Versatile] There are professional glass and tile drill bits in this drill, which can provide glazing and precise drilling on tiles, marble, thin iron plates, mirrors and glass, reducing the damage caused by breaking.Specification:Item Type: Bit SetProduct Material: YG6X Cemented CarbideGross Weight: Approx. 78g/2.8ozProduct Model: 3mm/0.12in, 4mm/0.16in, 5mm/0.20in, 6mm/0.24in, 7mm/0.28in Drill Bit Package List:5 x Home Improvement Tile Drill Bit (1 x 3mm Drill Bit, 1 x 4mm Drill Bit, 1 x 5mm Drill Bit, 1 x 6mm Drill Bit, 1 x 7mm Drill Bit )Note:Remember to add water or coolant when drilling.