Vacuum Valve 12mm 1/2"

Vacuum valve with 12mm (1/2") hose connections. Acts as siphon breaker to prevent water intrusion through sea water intake with severe damage as result. Installed above water line between heat exchanger and the exhaust hose. Non corrosive, proven design made of tough thermoplastic with rubber valve. Easy to install. Interchangeable with Johnson Pump 09-47316-01.