21 1/4x21 1/4x1 Exact MERV 14 AC Furnace Filters 20x21 1/2x1 which are 1/1000 of a

which are 1/1000 of a millimeter (a human hair is about 70 microns wide)

The effective life of your air filter depends on both the inside and outside conditions of the environment in which the filter is being used

pet dander

Nordic Pure 20x35x2 Trane Replacement RTU ( Roof Top Air Handling Unit) MERV 12 Plus Carbon air filters are made of a dual material where the MERV rated material has been fused together with a carbon layer

21 1/4x21 1/4x1 Exact MERV 14 AC Furnace Filters 20x21 1/2x1 which are 1/1000 of aActual Size: 21 1 4 x 21 1 4 x 3 4 (21. 25 x 21. 25 x 0. 75) Airborne dust, pollen, mold spores, pet dander, smog, dust mite debris, smoke, and bacteria are captured and removed. Ideal for customers with health problems or for commercial units which support a rating of MERV 14 and above Hypoallergenic, antimicrobial, and electrostatic filter media. Moisture resistant frame. Nordic Pure MERV 14 is equivalent to MPR 2800 Made in the USA. Nordic Pure