13x21 1/2x1 Carrier Replacement Filter by Aerostar - MERV 8, Box of 12 Replaces Bryant/Carrier part # KFAFK0112SML Fits HVAC Unit Models: Carrier: 018/024, FV4, FK4, FC4, FB4, FA4, FH4, FA4ANF024, FA4BNC024, FA4BNF024, FB4ANF024, FB4BNF024, FC4CNF024000AAAA, FX4CNF018 (1.5 - 2 Tons) Bryant and Payne: FV4, FK4, FC4, FB4, FA4, FH4, PF1MNC018, PF1MNC019 (1.5 - 2 Tons) Pleated MERV 8 Media Comparable to MPR 600 and FPR 5 Designed for Superior Filtration Efficiency Made with electrostatically charged synthetic material that draws and captures allergens between 3 - 10 microns, including lint, dust mites, spores, pollen, pet dander, and dust. Reduce Cost An Aerostar furnace air filter helps keep your HVAC unit working efficiently by removing dirt and reducing strain on the motor. When your unit runs properly, it consumes less energy, requires less maintenance and will have a longer life. These factors will have an impact on your utility bill and maintenance costs. It is recommended that you change the filter every 60 to 90 days during normal times of year but increase frequency to 30 days during peak summer and winter months when your unit is working the hardest. About Aerostar Air Filters Aerostar filters are manufactured in the USA by Filtration Group, a world-leading manufacturer and supplier of filtration solutions for residential, commercial and industrial applications. The Aerostar brand is known for constantly innovating and improving their technology to help make filtration more efficient, effective and environmentally friendly every day. Whats in the Box Box of twelve Aerostar MERV 8 Pleated Furnace Air Filters. MERV 8 filters are comparable to MPR 600 and FPR 5 ratings