Hyaluronic acid for hair, which retains 1000 times its weight in water and is an essential ingredient to maintain the natural moisture barrier of your scalp and strands. This potent hydrating active weightlessly coats hair to keep it feeling hydrated for up to 72 hours, and helps hair look visibly plumped, bouncy and shiny. USAGE INSTRUCTION: Apply to hair lengths and tips and leave overnight. No need to rinse, no residue and no weigh down the next morning. Washing your hair is optional. Discover an exclusive night ritual enriched with hyaluronic acid to instantly infuse hair with deep hydration and seal cuticles overnight without any weigh down. Wake up to hair that is soft, detangled, and frizz controlled. First of its kind overnight technology created in the L’Oreal Laboratories gives you 4x more moisture in just 1 night, keeping your hair hydrated, shiny and bouncy.