The Atmos cleans your air two ways at once. A 3 layer True HEPA filter traps dust, pollen, pet hair, smoke and smells down to 0.3 microns. At the same time, it releases 20 million negative ions to help clear the air. It's quiet, just 22 dB on sleep mode, runs on USB-C power, and is small and light enough to carry from room to room.