• Glass Nano Nail File: Spa-Rific's Nano Nail File 3pc set is the latest upgraded version of glass nail files, made of high-density nano glass, which skin doctors highly recommend. This heavy-duty set of files is the perfect tool for both men and women and is reusable for the continuous care of your nails. Achieve shiny and smooth effects and eliminate the typical rectangular nail files that damage the nails' surface and unhealthy chemical nail polish.