I have used this twice.  It's like big grains of salt that rub against your scalp but it does not hurt.  I know that it works because I have some psoriasis.  I use a tar based shampoo when I get breakouts on my scalp and while it helps/works, it's not the best smelling.  The CP-1 scalp scaler removed some of the extra skin that was forming (I used it as I was starting a psoriasis flare-up).  My scalp did not feel so bumpy after using this so I knew that it had removed some of the extra skin.

NB: I took a chance using this on psoriasis.  They do not claim to help with psoriasis.  I do not want anyone to get hurt because of my review.  For me, it worked.  It removed most of the extra skin that was growing because of psoriasis.  It's not a cure and I will still need to use the tar shampoo and my prescription but removing the extra skin lets my prescription medication and my tar shampoo penetrate better from what I've noticed.  

For those without psoriasis, it removes dead skin.  It does what it's meant to do.  It feels nice and refreshing.