Parker provides the industry's widest selection of check valves, available in a variety of end connections. Our valves are used in a diverse range of applications, from air and fuel systems to load holding. Our check valves utilize a variety of media including oil, air, and water and are made from materials such as aluminum, stainless steel, brass, and carbon steel. Parker check valves employ economical metal seating or zero-leak seating, with elastomer seals using a custom-molded seat design.