Bain Extentioniste for strengthening the hair fiber. Thanks to the Bain Extentioniste by Kérastase you can give your weakened hair fibers back their strength, cleanse them and make them shiny. This shampoo by Kérastase also accelerates your hair growth and thus ensures long and healthy hair. Enriched with valuable ingredients such as Creatine R and Taurine, the shampoo increases the resilience and resistance of the hair and are responsible for a healthy scalp.