Matrix Biolage Advanced KeratinDose Pro-Keratin Renewal Spray is a revitalizing treatment that repairs over-processed hair damaged by chemicals or mechanical stress. Enriched with a paraben-free formula with Pro-Keratin and Silk, it deeply nourishes hair, leaving it renewed, soft and shiny. Spray onto towel-dried hair, comb and style as usual. Do not rinse. Spray onto dry hair to add more hydration and shine.