The Resistance Extentioniste Masque Extensioniste by Kérastase is a strengthening hair mask that was developed especially for long hair. This product is the perfect choice for you if you particularly suffer from hair breakage and split ends. The hair mask has a caring, strengthening and regenerating effect and supplies the hair fibre with important keratin. The maleic acid strengthens your hair from the inside out and thus provides greater elasticity and bounce. In addition, the Resistance Extentioniste Masque Extensioniste by Kérastase seals your hair and protects it from hair breakage and split ends.