What it is: An advanced vitamin C serum that helps firm the look of sagging skin, improve skin tone and decrease the appearance of fine lines and wrinkles.Who it's for: All skin types.What it does: This gel formula utilizes a high concentration of two distinct types of vitamin C that work synergistically to provide long-lasting benefits. It increases skin's luminosity while minimizing the appearance of hyperpigmentation. It is specifically formulated to deliver the best results with the highest-quality vitamin C. How to use: Use nightly after cleansing and toning; apply sparingly to face, neck and décolleté. Massage well before applying moisturizer.