Nordic Pure Pleated Air Filters MERV 7 are designed to filter out lint, dust, pollen, pet dander, dust mites, bacteria, and mold spores using electrostatically charged synthetic materials. Each filter features a moisture-resistant frame and metal mesh support, ensuring durability and efficiency in HVAC systems. These filters improve air quality and system performance, capturing particles as small as 3.0 microns. To maintain optimal efficiency and fresh air, replace the filter every 30-90 days.