Tight Cellular Junctions Technology: Hyaluronic Acid Fragments ensure epidermal cohesion to infuse and lock water in for ultra long-lasting hydration. Hyaluronic Acid, a powerful moisturizing active ingredient, combined with high concentrations of La Roche-Posay thermal spring water, fills the skin with moisture for 24 hours: The skin is infused with water. The skin barrier is strengthened and durably retains water in the skin.