Utoolmart 22mm Diamond Drill Bit Hole Saw for Tile Glass Marble Granite Fiberglass Ceramic Tool 2pcs

High performance in cutting glass, slate, tile, porcelain etc. Tiny diamond particles coated tip offers sharp cutting. To prolong its using life, please remember to keep it with coolant sometimes. Instructions for use of glass hole opener: 1. Put the hole opener into the electric drill before use and confirm that it is firmly clamped before it can work. The hole should be smooth and do not apply side pressure and curve to drill. 2. Sufficient cooling and lubrication is required during continuous work, which has reduced the impact of product wear on use. 3. Workers need to wear corresponding protective equipment to protect workers from working safely.