HTH 51437 Super Select Shock Treatment for Swimming Pools， 1-Pound Bag， 5-Pack<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Bacteria killing</li><li>Algae destroying</li><li>Fast Dissolving</li></ul></div><img src="http://ecx.images-amazon.com/images/I/51o4gMk28aL.jpg" noproxy>