Up to 3 months of filtration performance. Electrostatically charged. Attracts Microscopic dust and allergens. Arm & Hammer the standard of purity. 87% Reduction of large airborne particles. Allergen defense. Reduces: Pollen, mold sport, pet dander, dust mite, microscopic allergens. Dust, Household lint. Odors, smoke, VOC's. Plus odor reduction. Date of installation.