Keep your home purification system in perfect condition by replacing the air filters every 6 months or 3000 hours. When the time comes to make the switch in your Medify Air MA-40 Air Purifier, trust the Medify Air H13 HEPA Replacement Filter Set to keep your air clean, clear, and breathable. This air purifier replacement filter set contains 2 filters compatible with the Medify Air MA-40 Air Purifier only (unit not included). Designed to keep your air clean, these air filters are a higher grade of HEPA. This means the filter removes 99.9% of particles down to 0.1 microns. This air purifier filter pack uses a 3-stage system with a pre-filter, HEPA H13 media to eliminate harmful particles, and an active carbon filter that removes unsavoury odors throughout your home. Breathe easier and comfortably in your home by replacing an old or dirty air filter with the Medify Air MA-40 H13 HEPA Replacement Filter.