For the ultimate in convenience, choose Assembled Whisper® Bio-Bag® Cartridges.
Like the unassembled, the packages are color-coded, making it easier than ever to remember which size to purchase.

Sizing:
Small -3i Internal
Medium - PF10 Power Filter, 10i Internal and Reptofilter 90 GPH
Large - 20, 30,40 and 60 Power Filters and 20i & 40i Internals