Strengthening care for slow-growing, damaged hair lengths. Kérastase Resistance Bain Extentioniste shampoo supports strong hair growth from the roots. Weakened hair prone to breakage is strengthened as its internal structure is rebuilt and sealed to provide greater protection throughout its growth. This cleansing shampoo is enriched with Creatine R, an active complex designed to increase resistance and elasticity, and taurine, an amino acid that supports a healthy scalp. Hair is thoroughly cleansed to reach its ideal healthy length in perfect condition.