
There are various types of check valves used in a wide variety of applications. Check valves are often part of common household items. Although they are available in a wide range of sizes and costs, check valves generally are very small, simple, and inexpensive. Check valves work automatically and most are not controlled by a person or any external control; accordingly, most do not have any valve handle or stem. The bodies (external shells) of most check valves are made of plastic or metal.

Usual uses of check valves:
Water & waste pumping systems
Pipes
Sewer system
Heating unit
Fire pipes
Marine & Naval industry
Oil & gas pipelines
Flush bathroom systems