1、The product is an quality tool fordrilling holes in tiles, glass, fish tanks, marble, granite countertop, ceramic, porcelain, ect. 2、Our hole saws are taller than most other available products. You can drill through thicker materials with our tools with ease. 3、These diamond drill bits are made of high quality material to resist corrosion. A thicken diamond coating on the tops offers superior cutting strength for maximum drilling outcomes. 4、These glass hole saw set along the drill bit facilitate the entrance of cooling water and escape of chips and other particles from drilling, thus making the drilling process easier. 5、Diamond hole saws are designed and constructed by unrivalled knowledge and expertise of brazing and coating edges and surfaces with the very hardest of materials Features: Easy to use, Good Performance and long life Excellent for making clean and accurate hole on glass, tile, granite and marble Works better with a electric drill ( Excluding in this item ) Specification: Material: Diamond Color: Silver Size: 18mm Package included: 1 x Glass Hole Saw Notice: 1.Please allow 1-3mm error due to manual measurement pls make sure you do not mind before you bid 2.The colors may have different as the difference display,pls understand