In today's indoor enviroments, pollution levels often exceed those in outdoor air. Medical studies report that our respirtory system may have to eleminate up to two heaping tablespoons of particulates everyday. Dust, pollens, mold spores, pet dander, carpet lint, and dust mite feces are some or the pollutants we inhale. Breathing air bourne pollututants often triggers allergy, asthma, and hay fever symptoms. Quality Comfort recommends a great product by Dust Free®. These air filters are Doctor recommended, easy to maintain, and has a life time warranty!