Most of the devices are suitable for all types of hair. You just need to adjust the temperature carefully — lower for the fine hair and higher for the coarse and thick hair. The brush works great for the curly, wavy and frizzy locks. In fact, there are so many brushes that are good at straightening any hair type that it’s hard to choose the best hair straightener for curly hair or the fine one. The straightening hair brush is also suitable for the hair that is slightly wavy or almost straight but keep in mind that in this case, the final outcome may be not so impressive. By the way, if you have really thick and dense locks which are pretty hardtop manage I highly recommend you to use some oil for the better result.