Great for undercoats and simple mats
I bought this because my cat went out the snow and got a bad case of matted fur.  It actually took out a lot of undercoat fur and detangled simple mats, which is good as we are coming out of winter and he is shedding like crazy. Unfortunately, it will not take care of clumpy/severe matts. I am slowly shaving/cutting those off my cat so he can start with a fresh fur this spring. I am still rating it a 5 star though bec I do not think it was meant for severe/clumped matted fur that's close to the skin.
Rating: 5 stars