Get noticeably fresher, allergen-free air with this deep pleated furnace filter from Filtrete. Designed specifically for residential use, these filters effectively attract and capture smoke, smog, household dust, mould spores, and pollen. These filters feature 1-inch pleats to provide more effective filtration than comparable fibreglass filters, washable filters, and non-electrostatic filters. For best results, make sure to change your filter every 90 days. These pleated filters have a Microparticle Performance Rating (MPR) of 1000. Each filter measures 20 in. x 25 in. x 5 in.