L'Oreal Serie Expert Inforcer Masque is an intensive strengthening anti-breakage mask for weak hair that tends to break. Hair will be brighter, suppler, easier to style and protected from mechanical or thermal stress. Benefits Stronger hair. Smoother, softer hair. Brighter hair. More manageable hair. Technology Strengthening formula: Vitamin B6: an antioxidant barrier for lengths and scalp that protects hair from external aggressions. Biotin (a strengthening protein), for repairing weak and brittle hair instantly. How to use After L'Oreal Serie Expert Inforcer Shampoo, apply a walnut-sized amount of product to towel-dried hair (only lengths). Leave in 5 minutes. As an intensive treatment, do no use it more than twice a week.