Top positive review
a must have if you own an air pump.
on 29 May 2017
If you own an air pump then you should own a non return valve. It stops the water syphoning backwards down the tubing into the pump when you turn the pump off or ie when electric goes out etc. A must have product specially as they aren't expensive, if water is able to syphon backwards it will end up in the air pump and that could cause electric shock, fire, flooding. So a must have if you have an air pump. Would recommend.