Check-All Valve Mfg. Co. manufactures a complete line of in-line spring-loaded piston-type check valves. Many series are available which provide check valves for practically every service application. Valves are offered with metal-to-metal or soft seats in sizes ranging from 1/8-inch NPT to 20-inch flanged connections. Pressure ratings are available from full vacuum to 10,000 PSI. Standard or exotic materials are available, and you can choose from a wide variety of spring settings for any valve. Most options are available with fast delivery. CE/PED Compliant, CRN Registered, ISO 9001 Certified.