Hyaluronan (HA) is a glycosaminoglycan composed of repeating disaccharide units of N-acetyl-D-glucosamine and D-glucuronic acid. HA is abundant in synovial fluid, skin, the umbilical cord, and the vitreous body, where it exists as unbranched polysaccharide chains. Each vial contains 3 mg (H2) or 10 mg (H2-10) of lyophilized sodium hyaluronate. The average molecular weight is 1200×103-1600×103. The attached Certificate of Analysis provides the actual measured values for each product specification.