OBAGI Professional-C® 10%, 30 ml, Skin Serums for Women, The OBAGI Professional-C® face serum is a product full of active ingredients, meaning it provides absolutely luxurious care for your skin. Characteristics: protects skin against free radicals brightens helps to smooth out wrinkles and fine lines How to use: Dab an appropriate amount of the serum gently into clean skin with your fingertips.