By exhibiting optimized toughness, rigidity, and clarity while reducing or eliminating stress cracking that often occurs at interface, Apex SCR™ medical-grade PVC compounds enable rigid PVC to replace polycarbonate (PC) in clear medical components. Prolonged contact periods of 1–2 ½ weeks or more were required during tests to exhibit stress cracking. Able to be sterilized by gamma, EtO, and heat methods, these heat-stable compounds meet several biocompatibility standards.