Leave it in, Macadamia Professional’s Nourishing Moisture Leave in Protein Treatment. This spray is designed to strengthen, replenish, and protect. It leaves your hair healthy, shiny, and conditioned. It also protects hair to prevent future breakage by increasing elasticity. They use a premium protein blend of soy , quinoa and potato protein, as well as African Baobab Extract. Of course there’s plenty of Macadamia, and Argan oil. So get with Macadamia to improve your hair, and therefore your life….;)