Diamond Hole Saw Tile Ceramic Glass Porcelain Marble Drill Bit- This is a brand new item- Easy to use， high quality. good performance， long life- Excellent for making clean and accurate hole on glass ， tile and marble- Works better with a electric drill( Excluding in this item )When using the bit please add water to cool down the temperature to extend its service lifeSpecifications:Material: MetalSize: 6 / 8 / 10 / 12 / 14 / 16 / 18 / 20 / 22 / 25 / 28 / 30 / 35 / 40 / 45 / 50mmPackage Includes:1 x 16pcs Diamond tool drill bit hole saw set