HyperHEPA filtration proven effective down to 0.003 microns * Guaranteed total system efficiency of 99.5% for particles of all sizes, including ultrafine particles that others miss * Covers up to 1,240 square feet * Sophisticated control panel to easily control automatic operation via a programmable timer * This is a 120V 60Hz product version that is only safety approved for usage in North America and not suitable for overseas countries with 220-240V power supply