AGENYX Skin Renewing Vitamin C Serum – Hyaluronic Acid, Ferulic Acid & Vitamin E, 1 fl oz (30ml). Give your skin a radiance boost with the AGENYX Vitamin C Serum. Formulated with a powerful blend of antioxidants, hyaluronic acid, and ferulic acid, this lightweight serum is designed to visibly enhance skin radiance and promote a more balanced, even-looking tone.