Penn-Plax® Check Valve w/Air Filter for Aquariums | Best Product ...
Penn-Plaxยฎ Check Valve w/Air Filter for Aquariums Penn-Plax® Check Valve/Air Filters are perfect for use with your aquarium air pumps & accessories. The air filter provides clean air to your pump removing small particulate matter that may clog air stones or other air devices. The check valve engages whenever your air pump is off or in the event of a power outage stopping water from siphoning back into your air pump and preventing possible water damage. , Brand Penn-PlaxKeeps your air pump safe from water damage.