I bought this specifically for my shoulder which is going through physio at the moment. Unfortunately, this simply doesn't mould or fit to the shoulder at all.
Other than that, the ice pack is too big for the sleeve, meaning you have to fold over the top to squash it in so the velcro can close. The material that separates the skin from the ice pack is too thin so you need another layer as well.
It probably works fine for larger muscles such as in the legs and arms but I've got back to the old bag of peas for my shoulder.