With its slim, space-saving tower design, this mini air purifier offers out-of-the-way placement while effectively delivering cleaner, healthier indoor air to rooms up to 80 square feet (8 by 10 feet). Choose from three speed settings: low for quieter operation, medium for continuous use, or high for poor air-quality conditions. The unit's PERMAtech filter with HEPA media removes up to 99-percent of airborne particles, as small as two microns, from the air that passes through it for a CADR of 52 for smoke, 50 for dust, and 50 for pollen. To help freshen the air naturally, the unit also offers an optional ionizer, which releases negative ions into the filtered air. The negative ions then connect with positively charged particles to form larger particles that can be more readily picked up by the filter. The permanent filter never needs to be replaced, and it cleans easily with the brush attachment of a household vacuum cleaner. The air purifier measures 11-1/2 by 8-1/5 by 17 inches and carries a five-year limited warranty.