This 1 by 1 IN lead free dual check valve prevents the reverse flow of polluted water from entering into the drinking water supply at the service entrance or at individual outlets. It is designed for non-health hazard residential water system containment, continuous pressure applications and is to be installed immediately downstream of the residential water meter, in a vertical or horizontal position. The valve consists of a lead free brass body construction, with two plastic replaceable check valves, and stainless steel springs. The minimum working pressure is 10 PSI (69 kPa). The maximum working pressure is 175 PSI (12 BAR).