--- Strengthen hair from the inside out with Kérastase Resistance Bain Extentioniste. --- A fortifying shampoo that uses powerful amino acids and ceramides to improve elasticity from root to tip. --- Targeting weakened and brittle strands, the silky formula helps to rebuild the hair’s internal structure to make it more resistant to breakage, whilst a blend of lipids creates a smooth and shiny surface. --- The shampoo gently lifts away the build-up of dirt, impurities and excess oil from the scalp to leave locks fresh, clean and strong.