SkinCeuticals vitamin C, E and ferulic acid super serum is worth every single penny when it comes to results. The high concentrate formula contains a whopping 15 % of pure vitamin C, with 1 % vitamin E plus the addition of the antioxidant ferulic acid. Unlike many high concentration vitamin C products, this is gentle enough for sensitive skins. Simply pat on clean dry skin every morning. Then apply an hyaluronic serum plus a broad spectrum SPF.