La Roche Posay Kerium Extrema Softness Frequent Use.400ml. A highly smooth unique formula.. For 1ª time the Laboratoriaos The Roche Posay have integrated the Thermal Water in a shampoo that respects the hair and the hairy leather: Kerium Extreme Smoothness!! -A new technology lavante foamy, chosen by its properties softeners. -A pH physiological to assure a high tolerance. -A greasy and fresh foam to free the hair of all kinds of residues and to leave it clean and brilliant.