Tetra Whisper EX Carbon Medium Round Filter Cartridges, 4 Count, Fits Tetra Whisper EX 20 Fish Tank Filter

Tetra - Whisper Filter Cartridge Medium 4 PackTetra's New EX Filter Cartridges provide both mechanical and chemical cleaning of your aquarium's water. Includes new Timestrip Technology. Improved biological performance with Multi-Density Floss Continuous flush performance Round, modern design Replacement cartridge for Whisper EX20 Power Filter New Timestrips included with each filter cartridge