When decorating kitchen or bathroom walls, installing hold bars on showers, or drilling into mirrors and tiles, rely on the BISupply Diamond Masonry Drill Bit Set to get the job done without cracking your materials. Attach 1/4, 5/16, 3/8, 1/2, and 9/16in (6, 8, 10, 12, and 14mm) large hole drill bit to your angle grinder. Internal wax helps to keep ceramic tile drill bits cool while drilling. Water is recommended as an added cooling agent but not necessary to extend the life of your bits for stone, ceramic, porcelain, glass, and more. Align the diamond-crusted drill bit at a 30-degree angle from cutting surface and begin using low pressure. Slowly straighten to a 90-degree angle as hole starts to form for a smooth circular cut. Warning: This product can expose you to chemicals which is [are] known to the State of California to cause cancer and birth defects or other reproductive harm.