Watts LF7RU2-2 Dual Check Back Flo Preventer Valve, 3/4"The Watts LF7R Lead Free dual check series prevents the reverse flow of water through backsiphonage or backpressure. This ASSE 1024 listed valve is typically used to protect the water supply at the service entrance or at individual, non health hazard outlets where backpressure may occur. 3 4" Dual check valve Prevents the reverse flow of water through backsiphonage or backpressure Forged lead free brass body Forged brass provides strength and