i actually enquired bout this today there are 2 types chemical and chemical free my hairdresser suggested chem free for me anyway $300 should last 3-5 mths.... you get this stuff put on then hair is straighten with a straightener then you leave it for 3 days the wash with special shampoo cond which is part of the $300 she said its not like a perm where you see the regrowth, it just lasts ........ i'd love to do it but eeekk $300 our hairdresser does a wash, dry, straighten for $15 so i am happy with that for special occasions