The 1/2 - 2" Febco 880 Series backflow preventers began production in 1997 and was discontinued shortly after release. It is a testable, N-shaped, bronze body reduced pressure zone assembly with an inline check design. It utilizes a single access cover with plastic check modules, relief valve, and retainer. The relief is pressurized via an internal sensing line. The model 880U has factory installed union ball valves and utilizes the same repair parts.