I work with gemstone beads which are not always drilled precisely. Sometimes the hole is too small for the .18-size Beadalon I use. I used to throw these beads away, but now I enlarge the holes using these reamers. (They fit the matching handle, but you can use them alone.) Hand-reaming is slow, but it works. As shown in an instructional video, I immerse the stone in water while reaming. These are replacements, just in case -- but my original reamers are still good

Nothing is more frustrating then beautiful beads with too small holes. These replacements made quick work of enlarging holes on my lovely red coral beads!