Rock Tips Liquid Callus Formula

I found this to only be medium effective - it wore off my skin pretty fast, and took a long time to dry. It also stings alot if you happen to put it into a open would, no matter how small, on your finger.

I was hoping this could really toughen up fingernails too, however it doesn't. I think as a complete last ditch attempt to extend the life of severely worn calluses, yes it might help slightly, but not as much as you would want.