Filtrete 16x25x1 AC Furnace Air Filter, MERV 12, MPR 1500, CERTIFIED asthma & allergy friendly, 3 Month Pleated 1-Inch Electrostatic Air Cleaning Filter, 6-Pack (Actual Size 15.69x24.69x0.78 in)#1 Recommended Brand* (*Filtrete Brand is the most recommended brand of HVAC Air Filters based on the US Filtrete Brand Health Tracker, Ipsos, June 2022) The higher the MPR, the more microparticles such as pollen, pet dander, smoke, bacteria and viruses your filter will capture from the air passing through it FOR OPTIMAL PERFORMANCE of your heating & cooling system or HVAC system, change your home air filter at least every 90 days for 1 inch filters,