Deep Blue Professional ADB12111 2-Pack Air Stone for Aquarium， 1-Inch Cylinder</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>Durable air stone diffuses water in every direction</li><li>Assists in release of carbon dioxide build-up</li><li>Accelerates oxygen replenishment</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/41T-ztqLizL.jpg' noproxy></br>