11.5x23.5x1Pleat Filter

11.5" x 23.5" x 1", NaturalAire Standard Pleated Filter, Has An ASHRAE 52.2 Rating Of MERV 8, Convenient To Use & Easy To Replace, Ordinary Furnace Filters Are Designed To Protect Heating & Cooling Equipment From The Insulating Properties Of Relatively Large Airborne Particles, Removes Even Those Microscopic Particles That Can Stain Walls & Furnishings, Or Worse Aggravate Seasonal Allergies.