Covers almost 1100 square feet, is quiet, efficient, utilizes HEPA filtration. Removes allergens, pet hair & dander, contaminents & makes your air easier to breathe & healthier. If you live in an area prone to smoke from wildfires, this is a MUST HAVE. These are new in box, never used. Compare pricing with other large online retailers and you'll find these same filters selling for $50-$80.