FELLOWES 9324001 4-Pack Carbon Filter for AeraMax 100 Air Purifier Type: Charcoal Filter Used For: Air Purifier Odor Reduction: Yes Feature: Carbon Filter removes odors and captures large airborne particulates Compatible with Fellowes AeraMax 100 Air Purifier With normal usage, it is recommended that you change your filter every 3 months to keep your air purifier running at peak performance A filter change indicator on your Fellowes AeraMax 100 Air Purifier conveniently notifies you when it's time to replace your carbon filter