The Ordinary Hyaluronic Acid 2% + B5 Serum: Hyaluronic Acid 2% + B5 is a water-based formula combining low-, medium- and high-molecular-weight hyaluronic acid molecules and a next-generation HA crosspolymer to support hydration to multiple layers of your skin. It also targets the appearance of wrinkles and textural irregularities. Plus, it uses pro-vitamin B5 to enhance hydration at the outer layers, resulting in smoother, plumper skin.