Lee's 15/20 Economy Undergravel Filter， 1 Plate， 12-Inch by 24-Inch</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>Most economical of Lees three Under Gravel Filter styles</li><li>Filter plate has more open space which allows for better water circulation</li><li>Most economical of Lees three Under Gravel Filter Styles</li><li>Contains 1 filter plate that is made of a semi-flexible， break-resistant plastic</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/512kexVdhTL.jpg' noproxy></br>