Obagi C20 Serum 20% Vitamin C Made in JapanThe Obagi C20 Serum is a highly concentrated vitamin C serum designed to brighten skin tone and reduce the appearance of dark spots, discoloration, and hyperpigmentation. It contains 20% L ascorbic acid, one of the most potent and stable forms of vitamin C, to powerfully combat signs of aging caused by environmental damage and promote collagen production for firmer, younger looking skin. Key Features: Contains a high 20% concentration of L ascorbic