the large majority of us do NOT use any type of matt brush or whatever, we also do NOT use slickers. There are a few people that use a SPECIFIC type of slicker brush during blowing coat, but it is not an 'everyday' grooming tool recommended to use on a havanese coat. If you want to grow your hav out, you have to commit to COMBING (not brushing/dematting) to the skin every.day. there is no 'quick fix' magic grooming tool.
The magic comes when you put the work in.
