Dremel 663DR 1/4 inch Glass & Tile Core Drill Bit w/ Cutting Oil. Diamond-impregnated core-style bit is for drilling in both flat & contoured surfaces. Diamond grit a full 360-degrees around circumference of bit allows it to be used in a rasping action to enlarge a hole. Holes on sides of bit allow the removal of glass dust. Each bit packaged w/ cutting oil to increase speed of cut & prevent damage to bit from overheating. Use on glass, ceramic wall tile, glass block, glass bottles, jewelry.
