The Everlasting Crystal Nail File's uniqueness lies in the micro-fine unlimited glass filing surface. Much kinder to your nails than an emery board. It is so velvety smooth. It has a subtle filing surface that helps prevent nails from splitting and also gives accurate shaping. Suitable for natural and artificial nails, the Everlasting Crystal Nail File (made from specially hardened glass) is virtually unbreakable when handled properly. It makes filing your nails a pleasure.