US Patent 7357023 Modular inserts comprising check valves for flow meters

The present invention relates to an apparatus and method for upgrading fluid meters with improved modular check valve technology. The check valve module is secured within the meter using only external fasteners. The check valve module may also include a seal. The seal may be inspected by simply removing the external fasteners securing the check valve module within the enclosure and removing the check valve module from the enclosure. The check valve module may include a test port for testing the operation of the check valve.