1. Dual-acting fuction for air release and vacuum relief automatically.

2. Discharge air when irrigation system start on, and intake air when shut off.

3.  Installed on the highest point of irrigation watering system to minimize the collapse of mainline and submain pipes

4.  Reduce the chance of water hammer caused by a sudden reversal of water flows.

5. Allow air to escape during system start-up and prevent air restrictions.

6. Trapped air bubbles can damage pumps (via cavitation) and disrupt flow rates and pressure.