It's an OPI nail file which is known as the best nail file in the market. Give your nails a professional, clean and smooth appearance with this OPI Crystal Nail File. It's made of hardened glass with an everlasting abrasive surface that remains permanently etched into it. The OPI nail file is small in size so you can carry it in your hand bag, pass or pocket. The opi nail file can be used by both male and female, the opi nail file is original and that makes it long lasting and it will give you the best results.