The HemCon® Bandage PRO works by becoming extremely adherent when in contact with blood. This adhesive-like action seals the wound and controls bleeding. HemCon products are fabricated from chitosan, a naturally occurring, bio-compatible polysaccharide. Because chitosan has a positive change, it attracts red blood cells, which have a negative charge. The red blood cells create a seal over the wound as they are drawn into the bandage, forming a very tight, coherent seal. In addition to providing hemostasis, HemCon dressings also offer an antibacterial barrier.