Grifon Router Replacement Bit 3/4 inch (φ19mm) fine-tooth fine bit, approximately #220 grit. With its fine grit, this bit produces almost no chipping when grinding glass, preventing chips from protruding even when using narrow tape, allowing for fine solder lines. Also ideal for grinding mirrors. Inexpensive router bits tend to have rotational wobble, but this high-quality bit has no rotational wobble, enabling stable grinding. Stained Glass Router Router Replacement Bit