COSRX The Vitamin C 23 Serum is a hypoallergenic serum with a high concentration of 23% pure vitamin C. It acts as an antioxidant brightening booster, targeting early signs of aging. The serum effectively fades acne scars, hyperpigmentation, and dark spots, while brightening dull skin. It also works to firm, plump, and diminish fine lines and wrinkles, making it ideal for those with uneven skin tone and looking to restore youthful radiance to their skin.