The lead free Apollo™ Model DUCLF4A (4ALF-300) Dual Check Valve prevents backflow by either backpressure or back-siphonage from a cross-connection between potable water lines and substances that are objectionable, but not health hazards.
Apollo™ Backflow Preventer, Series: DuCLF4A, 1/2 in Nominal, FNPT, 175 psig, 33 to 180 deg F, Double Check Backflow, Media: Water, Bronze Body, 4.38 in L x 2 in H