Hyaluronic acid, with its high molecular weight, provides moisture, enhances the skin's natural barrier repair system, while also promoting tightening, lifting, calming, and hydrating for dry/sensitive skin. Medium molecular weight hyaluronic acid stimulates the skin's natural defense system and NMF (natural moisturizing factor), making it the ultimate ingredient for restoring moisture to dry and damaged cells, while also working against inflammation and irritation. Low molecular weight hyaluronic acid encourages the production of natural hyaluronic acid, accelerating and regulating the skin's natural cell renewal process. Benefits: -Anti-aging -Firms and smoothes the skin -Reduces wrinkles and fine lines -Restores skin's elasticity -Improves natural skin repair -Increases moisture in the facial skin -Soothes the skin Directions: Apply morning and evening after deeply cleansing the face with AHA Deep Cleanser. Gently spread a small amount of serum over the face and neck. For best results