Strengthens weak, overworked hair. Matrix Biolage Fortetherapie Fortifying Leave-In Treatment strengthens & repairs with restorative ceramide. Hair is left detangled, frizz free & more manageable. Directions for use: Shake well. After Matrix Biolage Fortetherapie Fortifying Conditioner, spray Matrix Biolage Fortetherapie Fortifying Leave-In Treatment evenly on damp hair. Comb through. Style as usual.