Flanders PrecisionAire 10255.011824 18 by 24 by 1 Flat Panel Heavy Duty Spun Glass Air Filter<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Metail media retainers on both sides for maximum strength</li><li>Keeps equipment clean for efficient opertion</li><li>Change filters monthly for peak energy efficiency</li><li>UL Class II</li><li>Maximum air flow</li></ul></div><img src="http://ecx.images-amazon.com/images/I/61QSN5aRwQL.jpg" noproxy>