La Roche-Posay Thermal Spring Water is scientifically proven to have soothing and protective properties thanks to its richness in selenium and trace elements and promotes skin health by reducing rashes. For these unique benefits we have made it a key active ingredient in our products. Thermal spring water from the #1 thermal dermatology centre in Europe: has treated the skin conditions of more than 450000 patients since its creation in 1905. This water has natural prebiotic properties: it rebalances the skin microbiome to promote its health. How to use: An ultra-fine mist spray that allows micro-droplets of water to penetrate the skin immediately. - Spray as often as needed. - Leave on for 3 minutes then pat dry without wiping. - Store in the refrigerator for a cooling effect.