The 1 Inch Plastic Body Continuous Acting Air Release & Vacuum Relief Valve is designed to efficiently expel trapped air and allow air entrance during vacuum conditions in irrigation and water pipelines. Made from durable, corrosion-resistant engineering plastic with a male BSP/NPT threaded inlet, this valve withstands working pressures up to 175 psi. Its continuous acting mechanism ensures the release of residual air even under pressurized conditions, preventing water hammer, air locks, and pipeline damage. The valve closes tightly to prevent leaks once the pipeline is full of water. Supplied as a pack of two for convenience, this valve is ideal for agricultural irrigation, landscaping, and greenhouse applications where maintaining optimal water flow and system protection is critical.