Protect your aquariums air pump with this precision engineered check valve. Allows air to pass in one direction only and prevents water from siphoning back into the air pump in case of a power failure or during aquarium maintenance. Directions:
Install by cutting airline between air pump and first outlet. Position check valve with arrow pointing towards the aquarium and away from the air pump.
Satisfaction guaranteed.
If for any reason you are dissatisfied with this product, we will cheerfully refund you your money.