Q. What is L-ascorbic acid? A. The super antioxidant, known as the most potent and effective form of vitamin C to help provide antioxidant defense, brighten skin and soften the appearance of fine lines. Obagi's Professional-C® Serum ✔️ Fortifies skin's defenses against environmental stressors ✔️ Encourages skin to rebound from previous, visible damage ✔️ Helps restore skin's antioxidant strength to help skin appear younger for longer ✔️ Formulated with up to 20% L-ascorbic acid while leaving skin feeling soft #obagi #obagimedical #obagiobsessed #vitamincskincare #VitaminCSerum #ObagiProfessionalCSerum #onlyobagi