OPW Suction Equipment performs a series of specific tasks. Foot Valves are installed to maintain prime in suction-system fuel lines. Angle Check Valves are installed on top of fuel-storage tanks to maintain prime. Vertical Check Valves are installed directly below the inlet in the pump in the dispenser island to maintain prime. Suction Tube Extractor Fittings are installed on top of storage tanks to facilitate the extraction of the suction tube/foot valve assembly from the tank in a suction system.