The 664DR diamond drill FlipBit features superior long life compared to other diamond drill bits and its flute design is faster at eliminating material compared to core bits. Its one-of-a-kind FlipBit design lets you drill two hole sizes with one bit by simply flipping the bit over to select a different size. The FlipBit is ideal for drilling in both flat and contoured surfaces and can be used to enlarge holes and make small cuts. Makers will find the 664DR ideal for creating jewelry, ornaments, art and decor. The 664DR diamond drill FlipBit can be used on glass, ceramic wall tile, glass block, stone and glass bottles.