Kérastase Blond Absolu 2% Pure Hyaluronic Acid Serum 50mlHydrating skincare serum, now for hair! Blond Absolu 2% Pure Hyaluronic Acid Serum by Krastase is a hydrating, repairing blonde hair and scalp serum. Its the ultimate blonde repair serum for bleached blondes, as it contains Hyaluronic Acid with Krastase' highest concentration of Macro and Micro Hyaluronic Acid to repair the surface damage of hair and moisturise both scalp and hair. The lightweight texture of this clear gel serum preserves the scalp