Diamond hole saw bits are perfect drilling holes into specialty materials. They will cut and make perfect holes in:<br><br> Glass, ceramics, porcelain, ceramic tile, porcelain tile, limestone, slate, marble, granite, light stone and fiberglass. <br>Works great for bathroom and kitchen jobs when you need to drill for faucets or pipes. Also great for making drain holes in planter pots. <br><br> For Best Use: Tilt the bit until you get an indention or bite on one side then slowly return the bit to the center to finish. Be sure to add water during the drilling process to keep the bit and materials from burning.