Use this filter as a replacement for models AC3900, AC4000, and AC4000CA

The germguardian Tabletop Air Purifier has one combination replacement filter that combines several filtering technologies. A combination HEPA filter captures 99.97% of dust and allergens, and fights germs and unwanted odors. It is suggested that the filter be replaced every 6-8 months depending on use.
  • US Warranty 3 Year Warranty
  • Non-US Warranty: 30 days parts and labor