This great tool is for smoothing and enlarging holes.
Files and Reamers
Description
This diamond-tip bead reamer set includes a hollow aluminum handle with brass chuck. Three points included: 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. ALWAYS wet the point with water and then insert and turn it side to side until the hole is smooth or enlarged to desired size.