Large stone beads may have irregularly drilled holes. Sometimes I can't get .018-size Beadalon through one or two of the beads in a string. I used to throw these beads away, until I discovered that I could enlarge the holes with a reamer. This long one is suitable for beads up to 2" long; it fits the handle, or you can use it alone. It's slow but effective. Following directions from an instructional video, I do this work under water. I bought this as a replacement, but my original is still good.