Help rehydrate skin and boost skin's moisture levels by keeping skin healthy & hydrated with Timeless Skin Care Hyaluronic Acid Serum 100% Pure. Hyaluronic Acid can hold up to 1000 times its weight in water, making it the number one, go-to ingredient for hydration. This serum contains 1% pure Hyaluronic acid, the ideal concentration to effectively hydrate and boost skin's moisture levels.