CARX model composition type exhaust valve, the body is tubbish shape. Trim include SS float ball, lever and disc. This valve is installed on pump outlet or water pipeline,to remove air inside pipe, increase use efficiency of pipeline and pump , when happen steel pressure inside pipe, this valve resorb outside air into valve quickly, to avoid pipeline damaged due to negative pressure. When pipe start injecting water, disc is at open position, heavily exhaust, body fulled with water when rackup air, float ball rise and make disc close, stop exhaust, when pipe pumping normally, if little air collected to some certain inside valve, water line inside valve drop, air is exhaust through small hole. When water pump stop, water inside pipe flow empty or meet negative pressure inside pipe, chock plug quickly open, absorb air, ensure pipeline safety.