Nordic Pure 14x25x1 Pleated Plus Carbon MERV 12 rated air filters are made of a new dual material where the MERV rated material and carbon material are pleated together to form a formidable obstacle to dust and odors. Because the carbon is also pleated, there is 3 times as much odor-fighting capability in each filter. Each time air passes through a Nordic Pure pleated furnace filter, lint, household dust, pollen, dust mites, pet dander, smog, mold spores and germs from coughing or sneezing are removed. Our treated synthetic filter media prevents the growth of bacteria or mold, resulting in a much healthier living space. MERV 12 air filters are comparable to air filters with the MPR rating of 1500-1900, a FPR rating between Red and Blue, and an APR rating between Platinum and Diamond. Particles in indoor air are measured in microns; for scale, a human hair is about 70 microns wide. Each Nordic Pure 1 MERV 12 air filter will capture more than 90% of 3.0-10.0 micron contaminants and up to 90% of 1.0-3.0 micron contaminants. This high performance HVAC replacement filter will outperform non-electrostatic fiberglass filters, washable filters, poly disposable filters, and will help keep your air conditioning and heating systems running efficiently, saving you money on utilities and costly maintenance. The effective life of your air filter depends on both the inside and outside conditions in which you live and work.