Vacuum Release Valve With Restrictor is equipped with a restrictor. Two spool valves are built in. Vacuum suction and release can be controlled with a single valve. Each valve is equipped with a restrictor to enabe flow rate adjustment of released air. It provides vital protection to pipeline systems. They allow air to escape during system startup by preventing air restrictions, water hammer caused by large air masses, inaccurate flow meter readings. The Vacuum Release Valve With Restrictor is very efficient.