Upgraded Brass RV Vacuum Breaker Check Valve, 571-VAC-CHK-A Camper Trailer Flusher Check Valve fit for b&b Model 571 Check valve Replace Leaking Vacuum Breaker on Black Tank System 1/2 DN Male. Installed between the freshwater inlet connection and the tank flusher, this vacuum breaker valve allows black tank water to mix with grey water while keeping the freshwater source clean and healthy.
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