This is probably the only nail file I haven't lost, probably because I can't afford to lose it! It's like magic. It looks like other glass nail flies until you've actually tried it. It seals nails as well as protects them while filing. And it can be washed anytime with any soap (I use JJ Baby Shampoo) and germs and dirt can be removed from the file. The file doesn't lose it's roughness and always keeps nails looking amazing. The file is really long lasting, I have mine for 6 years now :)