This company offers a MERV 11 filter as a simple and cost-effective way to improve the air quality in commercial buildings. It includes a 100% synthetic, gradient density, non-woven media that is totally hydrophobic and enclosed in a strong double-wall beverage board frame. The filter has been independently tested and certified to MERV 11 (Minimum Efficiency Reporting Value) as specified by ASHRAE Standard 52.
Lennox Industries Inc., P.O. Box 799900, Dallas, TX 75379-9900; (800) 4-LENNOX.