Product Description The Flanders NaturalAire Standard Air Filter is made of a one-sided metal-reinforced pleated media. This filter tests as a MERV (Minimum Efficiency Reporting Value) 8 rating through ASHRAE 52.2 testing methods. Housed in a recyclable clay-coated moisture resistant frame, the NaturalAire MERV 8 Air Filter uses a mechanical media that maintains the minimum listed efficiency through the 90-day service life of the filter. This filter captures particles as small as 1 microns and is effective against the following contaminants: pet dander, mold spores, dust mite debris, pollen, household dust, as well as debris and lint. From the Manufacturer The Flanders NaturalAire Standard MERV 8 is made of a one-sided metal-reinforced Pleated media. This filter tests as a MERV 8 rating through ASHRAE 52.2 testing methods. Housed in a 1-Inch recyclable clay-coated moisture resistant frame, the NaturalAire MERV 8 uses a mechanical media that maintains the minimum listed efficiency through the life of the filter. This filter captures particles as small as 1 microns and is effective against the following contaminants; pet dander, mold spores, dust mite debris, pollen, household dust, as well as debris and lint.