Our quality diamond-tip bead reamer set includes a hollow aluminum handle with brass chuck. Three points included: 45 degree Edging Point smooths bead edges to reduce wear on string, cord, thread & wire; Small Reaming Point & Large Reaming Point - can both be used to straighten, smooth & enlarge holes in ceramic, glass, stone and other types of beads. Smallest point is .5mm, largest is 5.25mm. Here's how (BR600) works: 1) Loosen collet, insert the base of a point into the chuck and re-tighten. 2) Wet the point with water and turn it side to side until the hole is smooth or enlarged to desired size.