Professional-C Serum 15% Vitamin C Antioxidant Serum is formulated with L-Ascorbic Acid - the purest, most bioavailable form of Vitamin C - to help brighten and even skin tone, strengthen your skin's antioxidant defenses, and improve the appearance of fine lines and wrinkles. One full-size bottle for your daily routine at home, plus a travel-size companion so a weekend trip, work bag, or gym locker never means skipping your Vitamin C step. | Obagi Medical Brightening Duo: Professional-C Serum 15% | Dermstore