Credo Blade News Today

>> reporter: find out how dirty and dangerous nail salons can be. we are going in with a hidden camera. >> reporter: our friends at "20/20" went in with hidden camera. this woman uses a cotton ball on herself and then on the client. ew! files and buffers should be brand new every time. see what looks like white chalk here? thats a previous clients dead skin rubbed all over a new client. major no-no. but worst of all, illegal instruments. this razor called a credo blade is banned in 45 states. th...