Flanders 84858.011625 NaturalAire Standard Pleat Filter MERV 8, 16" x 25" x 1" Features: The NaturalAire Standard has an ASHRAE 52.2 rating of MERV 8.This filter is convenient to use and easy to replaceOrdinary furnace filters are designed to protect heating and cooling equipment from the insulating properties of relatively large airborne particlesThe NaturalAire Standard goes far beyond that, removing even those microscopic particles that can stain walls and furnishings, or worse - aggravateseasonal allergies.Lasts up to 90 daysSynthetic mediaWire backed media