Irrigation Air release valves General Features:Admits large volumes of air into pipe lines to prevent vacuum when drainingReleases large volumes or air from pipe lines when fillingPrevents suck back of mud and dirty water into pipe linesProtects irrigation systems and componentsDurable,Website:http://www.tupipe.com, weather resistant and non-corrosive materialRemovable top for seal maintenanceBright color allows easy visibilityIrrigation Air release valves Specifications: InletHeightClear open diameterSeal pressurePressure rating1" NPT or BSP178mm (7")Ф 19.7mm (0.775")7 Kpa (1 psi)1.03 Mpa (150 psi)1.25" NPT or BSP178mm (7")Ф 19.7mm (0.775")7 Kpa (1 psi)1.03 Mpa (150 psi)1.5" NPT or BSP242mm (9.5")Ф 29.0mm (1.140")7 Kpa (1 psi)1.03 Mpa (150 psi)2" NPT or BSP242mm (9.5")Ф 29.0mm (1.140")7 Kpa (1 psi)1.03 Mpa (150 psi)