A healthy home begins with cleaner air. To help you achieve this, Filtrete created this Allergen Defense micro allergen air filter to improve the air quality in your home. More specifically, this filter is specially designed to reduce airborne allergens. It uses electrostatic technology to attract and capture microscopic allergens like pet dander, smoke, and household dust. It's also effective for capturing large particles such as pollen and lint. It carries a Microparticle Performance Rating (MPR) of 1000. Plus, it delivers up to three months of filtering performance. Replace it every 90 days to ensure you and your household are breathing nothing but the cleanest air. This product outperforms fibreglass, washable, and non-electrostatic pleated 1-inch (2.5 cm) filters. Dimensions: 14 in. x 25 in. x 1 in.