Caleffi Backflow Preventer, Continuous, Series: 573, 1/2 in Nominal Size, FNPT, 175 psi, 32 to 210 deg F, Brass Body, 4-1/2 in W
The backflow preventer prevents contaminated water from back-shiphoning into the the potable water supply system. This may occur when the pressure in the potable water supply system changes causing water fl ow reversal. The backfl ow preventer is installed between the potable water supply system and the internal domestic water supply system, creating a safety zone which prevents the water in the two systems from coming into contact.