This is the Kerastase Premiere Decalcifying and Repairing Shampoo, formulated with Citric Acid and Glycine to address hair damage. It is specifically designed to soften the fiber, increase resilience, and reverse surface damage caused by hard water mineral deposits. Use this shampoo as the first step in your routine to gently cleanse the scalp and hair while actively beginning the repair process, preparing the hair to better receive subsequent treatment benefits.