Schrader Valve to Male NPT Fittings Adapters to Winterize Backflow Preventer and Pressure Vacuum Breaker for Sprinkler Systems

These fittings may be used to connect an air compressor or bike tire pump to a backflow preventer valve (a.k.a. pressure vacuum breaker) for winterization purpose, or wherever Schrader valve to male National Pipe Thread (MNPT) fittings are needed. Backflow preventers or pressure vacuum breakers (PVB) are typically installed in underground sprinkler systems to prevent water contamination in the event of a water pressure loss. Packaging is reusable. A generalized procedure to winterize backflow preventer using compressed air and bicycle tire pump is provided on the packaging.