As is somewhat common knowledge, crystal or glass nail files are the best type for your nails. They seal the layers of the nail better, which helps to prevent peeling, and they leave your nails very smooth. You can also use them back and forth instead of one direction across the tip of the nail.Many nail care brands carry crystal nail files, from Revlon to OPI, but the one that I chose was Sephora's. It comes in pink and purple, I got the purple. It is only a file on one side, with the other side being smooth, and it has a very fine grit. It works really well, and I really like it! The plastic sleeve that it comes in is kind of crappy, but it is a good file. It rinses off very easily and is easy to maintain.