Use the Beadalon Very Fine Pearl Reamer to enlarge and smooth out drill holes in pearls. The sharp, corkscrew-like file fits easily into the hole of any small pearl. Simply slide a pearl onto the file, and slide the pearl back and forth until desired interior diameter is reached. You will notice pearl dust as it cuts. Drill diameter: .60 millimeters (.024-inch) 5-inch (12.7 centimeters). Made in USA.