12 x Compatible Foam and Polycarbon Carbon Filter Cartridges to fit Fluval U2 Internal

Finest-Filters compatible replacement foam and polycarbon filter cartridges. These filter pads are compatible with Fluval U2 range of internal filters The plain filter sponges contain the biological cultures, biologically and mechanically filtering the aquarium water The polycarbon filter cartridges remove small particles from the water, and the activated carbon chemically filters the water of impurities Please Note: This is not a Fluval Product. This is a Finest-Filters alternative which serves the same purpose as the original brand.