The Vent Guard 14" x 6" replacement baseboard grille filters are effective for household dust, pollens, pet hair, dander, dust mites and carpet fibres. Disposable, they are easy to replace. Using these filters helps to keep heating system return ducts clean and extends the life of main furnace filter. Save time with these replacement filters that are made to fit, no cutting and fitting necessary. They are sold in pack of 4 and are protected by a limited warranty.