Instruct: Classify Amazon reviews into positive or negative sentiment
Query: I've done it.

I've actually used it on my natural nails, whether it says you can or not. I use it on low speed with a large stone bit (purchased seperately from Dremel -they have many bits available for their rotary tools). Keep in mind though that I'm a guy and I bite my nails(bad habit I know), but the tool helps me straighten them out.