Industrial Wafer Check Valves can be installed either vertically or horizontally; the only restriction is that the check valve must be properly seated with a minimal amount of back pressure. The majority of wafer-style butterfly valves are designed with four holes that line up with the pipeline they are linked to. Industrial Wafer Check Valves are compatible with most flange standards. They are used to permit and restrict liquid flow. These check valves need at least a certain level of fluid pressure in the system to function.