Hendrickson Bros Hose Thread Backflow Preventer
Backflow prevention devices are recommended with any irrigation system with a shared water source. The Hendrickson DG41 Backflow Preventer (Atmospheric Vacuum Breaker) is an economical choice to prevent the risk of backflow contamination from outdoor hose faucet connected devices. the DG41 is made of high strength ABS plastic for reliability and durability.
During normal operation the backflow preventer will appear to "leak" after the system or timer is turned off. This is normal as the backflow preventer is allowing water to drain from the system without entering the water supply. The amount of water drained will be equal or less than the water capacity of the drip system.
This fitting is not designed to be operated under constant pressure. It must be placed after any timers or valves in your system.