Tetra Whisper Assembled Bio-Bag Filter Cartridges</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>2 packages with two cartridges each</li><li>Ready-to-use， easy to assemble， and easy to replace</li><li>Ultra-activated carbon removes waste particles， odors， and discoloration</li><li>Keeps water crystal clear</li><li>Fits Whisper in-tank Filter 3i</li></ul></div></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br><img src='http://ecx.images-amazon.com/images/I/51Xnfke1kNL.jpg' noproxy></br>