4Pcs Small Aquarium Bio Sponge Filter with Suction Cups, Check Valves for 5 Gal,
Easy top set up & clean: simply install an airline into the unit and turn on the air pump, simply rinse and squeeze sponge in tank water. Size Up to 10 gallon 4 Pcs (Fanshaped). It is a great way to clean and oxygenate your fish tanks.