Holmes True HEPA Allergen Remover Tower Air uses true HEPA filtration which is up to 99.97-percent efficient in removing allergens such as pollen dust mold pet dander and smoke from the air passing through it. Unit features 3 speed settings optional ionizer and slim tower design. Recommended for rooms up to 150-square-feet; smoke CADR 100. Replacement filter: HAPF300D-U2. True Hepa filtration removes up to 99.97-percent of airborne allergens from air that passes through the filter; Washable pre-filter captures larger particles; 3 Speed settings provide options for different conditions and optional ionizer assists in particle removal; Filter life monitor alerts you when filter changes are needed to maintain maximum performance; Recommended for rooms up to 150 square-feet (8-feet by 10-feet); Smoke CADR: 100