Kérastase Masque UV Défense Active is an after-sun treatment created to repair coloured hair exposed to the sun. Your hair will be left soft & shiny with long lasting colour radiance. Masque UV Défense Active is formulated with Kérastase's Photo-Défense Filter which provides active protection against both UVA & UVB rays; cationic silicone which creates a hydrophobic barrier; ceramide to strengthen & reinforce the hair; & cationic derivatives to improve the surface of the hair.