Marina Airline Plastic Check Valve (1 Pack)
The Marina Check Valve prevents water from siphoning out of the aquarium through the air hose and into the air pump in the event of a power failure or when removing filters and other air-driven accessories from the aquarium.
Marina Part Number - A1165
Aquarium Kingdom Tips
Ensure a check Valve is used whenever an air pump is positioned at or below the waterline of the aquarium to prevent back-siphoning.