The Cosrx The Vitamin C 23 serum is a product that contains 20g of serum. The product is designed to help improve the appearance of the skin. The serum contains vitamin C, which is known to help improve the appearance of the skin. The product is also designed to help improve the appearance of fine lines and wrinkles. The product is easy to use and is applied to the skin using a cotton swab. The product is safe for all skin types. The product is