Feature:1. Hole Drilling: No watering required during drilling, and the hole also ensures neat and cut edge without burrs.2. Better Design: M14 thread design enables high torsion and bearing, not easy to slip, works with stability and .3. Practical Use: Allows for application in cutting holes on marble, glass, ceramic tile, granite and so on, very useful.4. 6Pcs in Total: There are 6pcs hole drill bit with 20mm, 25mm, 42mm, 50mm, 55mm, and 68mm diameter for your work needs.5. Good Material: Comes with even and thickened coating, rustproof, and very durable with wearing and long using.How to Use:1. Fasten correctly and firmly on the angle grinder. Turn on the angle grinder and let the bit spins in the air to check for balance. 2. Place the drill bit at an angle of 15‑45 degrees and drill down gently at an oblique angle. 3. When drilling about a semicircle, gradually raise the bit to the upright position, continue drilling and shake the machine slightly. Specification:Item Type: Hole SawMaterial: DiamondColour: GreenAperture: Approx. 20mm / 0.79in, 25mm / 0.98in, 42mm / 1.65in, 50mm / 1.97in, 55mm / 2.17in, 68mm / 2.68inHead Height: Approx. 15mm / 0.59inWorking Length: Approx. 40mm / 1.57inOverall Length: Approx. 60mm / 2.36inFemale Thread: M14Scope of Application: For marble, glass, ceramic tile, granite