??<br />Excellent workmanship? good aeration effect. Should be use together with air pump  <br />Air stone? its sand hardness is only lower than that of carborundum? white corundum etc. It is made in high temperature environment. Sturdy and durable? with great aeration effect? excellent filtration performance? widely used in:<br />1 fish ponds (aquaculture plants) increase oxygen for eutrophic water body in environment and biological culture. <br />2 increase oxygen for live fish and seafood transport? increase the amount of oxygen dissolved? prolong their lifetime<br />3 aquarium (purifiers) purification and filtration; water quality ozone sterilization and oxygen increasing. <br />4 sewage treatment plant for aeration and agitation? to prevent deposition of large particles of sediments and remove part of organic matters. <br />Name: round ring shape air stone<br />Model: AS050<br />Material: plastic + air stone<br />Color: blue<br />Size: ?85 x ?44 x high 25mm<br />1 x Air stone<br /><img src="http://img6.eachbuyer.com/x9/p100/by845_1.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/by845_2.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/by845_3.jpg" />                                                        <img src="http://img6.eachbuyer.com/x9/p100/by845_4.jpg" />