American Standard In-Line Vacuum Breaker, 1/2 in Nominal Size, NPT, Satin Nickel, Import
To prevent water from a handheld personal shower from flowing back into the clean water supply, simply install an in-line vacuum breaker between your wall supply and flexible shower hose. Installs between any wall supply and flexible hose on hand-held shower. Prevents back flow of water into supply piping.