Filtrete believes that a healthy home always begins with cleaner air. That's why they created this combo pack of furnace filters for every season. These electrostatically charged filters attach to your home's furnace to capture airborne allergens such as lint and dust from the air so that you and your loved ones can breathe better. For best results, remember to change your filter seasonally, or every 90 days. This pack of four filters makes that easy. A great way to improve the air quality in your home all year long! They even outperform other filter types, including fibreglass filters, washable filters, and non-electrostatic pleated filters. Filter dimensions: 16 inches x 25 inches x 1 inch.