Kerastase Masque UV Defense Active is an after-sun treatment created to repair coloured hair exposed to the sun. Your hair will be left soft and shiny with long lasting colour radiance. Masque UV Defense Active is formulated with Kerastase's Photo-Defense Filter which provides active protection against both UVA and UVB rays; cationic silicone which creates a hydrophobic barrier; ceramide to strengthen and reinforce the hair; and cationic derivatives to improve the surface of the hair. Protects from photo-degradation. Delivers protection against harmful UVA and UVB rays. Hair Mask For sun-exposed color treated hair.