That's what professionals say about Straightening Treatment, our most intense, most effective Keratin Treatment that smooths even the thickest, coarsest, most resistant hair. Featuring a unique proprietary Keratin Technology, Straightening Treatment deeply penetrates the hair shaft for maximum repair, while pure keratin and a unique blend of silk amino acids, organic shea butter emollients, and natural green tea antioxidants coat the hair to virtually eliminate dryness and brittleness, reduce excess volume and frizz, and deliver long-lasting nourishment and protection for up to 16 weeks. Safe for colour-treated hair. We can almost see you smiling you're welcome.