Cosmetic-grade hyaluronic acid (HA) has a molecular weight of 1200-1500 kDa, falling into the high molecular weight category. It is prepared through targeted bio-fermentation and precise purification processes. Due to its stable molecular structure, this molecular weight range places greater emphasis on skin surface protection and long-lasting water-locking functions. It can form a strong yet breathable moisturizing barrier on the skin surface, reducing moisture loss while isolating external irritants. It is a core ingredient for developing highly effective moisturizing and barrier-repairing cosmetics.