High-quality multi-function drill kit made of tungsten carbide, will not rust, prevent the drill bit from cracking, has a service life than the average steel drill bit, and is durable. drill bit makes drilling easier, less labor-intensive, and works at pressure. The process design of the spiral drain groove can chip removal, effectively prevent the retention of accumulated chips and work efficiency. The spear tip is designed with a sturdy hard alloy tip that penetrates a of materials. The custom triangular tip prevents slipping during punching and is easy to install. Normal impact drills, electric drills and drill bits can be installed and used. Assorted Size for various purposes, to meet the of your work. The masonry drill bit set penetrates a of materials such as tiles, glass, hard plastics, cement concrete, brick walls, wood, and reduces cracking. Materials with higher hardness are better for use with water. colour:blue Material:alloy Package Contents: 2*3mm Drill Bits 2*4mm Drill Bits 2*5mm Drill Bits 2*6mm Drill Bits 1*7mm Drill Bits 1*8mm Drill Bits 1*10mm Drill Bits 1*12mm Drill Bits Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.