Plastic check valves are used for a diverse range of applications. Transportation, chemical, car wash systems, water applications, pools and spas, medical equipment, and biopharmaceutical applications. The types of valves are various for the application. Diaphragm valves, duckbill valves, poppet valves, ball & spring known as ball checks, and Self-closing valves. Inline valves come in a number of thread and barb sizes, and for medical devices requiring luers, ISO 594 and 80369-7 and bond-in tubing sizes.