20mm/35mm/50mm are available to meet different hole diameter requirements, achieve precise hole expansion, and significantly improve work efficiency High-density diamond particle coating is used, the is and , and can quickly penetrate hard materials such as concrete, tiles, marble, etc. M10 thread interface is used, which can be easily connected to 100mm angle grinder; the package contains a special conversion rod that can be quickly adapted to use of handheld electric drills to meet needs of different construction scenarios. It integrates functions of drilling, hole expansion, chamfering, and polishing existing holes. It is widely used in various materials, including concrete, tiles, marble, , quartzite, and microcrystalline stone. Designed for precise hole opening, it can easily meet DIY and professional needs. The three-step size makes drilling operations time-saving and labor-saving Product name: Diamond Step Drill Bit Easy to install and use Packaging details: 2pcs Diamond Step Drill Bits 1pc Conversion rod Color: As Shown Material: Metal Package Contents: 1 set * diamond drill bits Only above package content, other products are not included. Note: Light reflection and different displays may cause color of item in picture a little different from real thing. The measurement allowed error is +/- 1-3cm.