Hand painted and decorated Bohemian Czech Crystal Manicure Files are designed and engineered for superior filing performance.Filing with back and forth strokes is allowed and highly recommended! It leaves your nail edges smooth and sealed, preventing cracking or splitting. Being authentic glass, the files are guaranteed not to wear out. The fine cut, one of a kind, elegant glass, is also environmental friendly. It can be washed, sanitized, and reused, in line with saving our earth, being very eco -friendly, not like the cheap throwaways. Being a functional product, the crystal manicure files are great gifts for all occasions, for anyone, any age! I have sold this product for the past 20 years, full time.