Arch Chemical 66501 HTH Metal Control， 1-Quart<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Helps prevent stains， scale， and cloudy pool water</li><li>One quart hth metal contro</li><li>Active ingredient-etidronic acid 20-30-percent</li></ul></div><img src="http://ecx.images-amazon.com/images/I/41xcu5WCwXL.jpg" noproxy>