Holmes AER1 Allergen Remover True HEPA Filter, HAPF300AH-U4R True HEPA filtration removes up to 99.97% of airborne allergens Ideal for those who suffer from allergies Captures allergens and pollutants: pollens, dust, dust mite debris, mold, pet dander, and smoke Compatible with aer1 ready air purifiers Replaces A Filter, D Filter, K Filter