Hagen 12-Pack Fluval Aquarium Filter Bio-Foam for A237/306 and 406 Models</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>Convenient 12 Pack</li><li>Includes 24 bio-foam pieces that fit Fluval 305/306/405/406 filters</li><li>Enhances biological filtration</li><li>Adds a second layer of mechanical filtration</li><li>Fluval A237 306， 406 Bio-Foam 24 pk (12x2 pack)</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/51Ybhr3AMoL.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/415E75sti9L.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/41F21rLMzGL.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/31n6rAH1g6L.jpg' noproxy></br>