A super-potent 15 percent vitamin C serum that firms, brightens, and improves signs of photoaging. designd to be mixed by you before its first use to maximize the ingredients' potency and keep the formula fresh. Reveals a brighter, firmer, and more even-looking complexion. Noticeably diminishes the appearance of signs of aging and photodamage. Formulated at a skin-friendly pH of 2.5