Tetra Whisper Bio-Bag Cartridge - Medium - 8 pk. - UnassembledTetra Whisper Bio-Bag Cartridge - Medium - 8 pk. - Unassembled Clear water made simple.They're tough on debris:Ultra-activated carbon absorbs odors and discoloration better than competing brands.Dense, dual-sided mesh catches debris and fish waste.More debris-trapping mesh than other products. Unassembled Whisper Bio Bags include packets of Ultra-Activated carbon for easy setup. Simple to setup and easy to use. This Medium Bio-Bag fits Whisper Power Filters 10i, E, J, 10, and Microfilter.Formerly known as Junior. Be sure to add me to your favorites list!