This is the replacement filter for the Model 4400 Aprilaire Air Cleaners.
The filter can also be used in the Models 2400 and 2140, provided the Upgrade Kit, part #1413 has been installed.
The filter is the heart of the air cleaner and needs to be changed once a year or when your Air Cleaner Control indicates it is time to change the filter. Use only genuine Aprilaire SelfSeal #413 to ensure the best performance of your air cleaner.
