Fanless and filterless, it helps make no noise and wishes no maintenance, but you need to remember to clean from the ionized dust that builds up in close proximity to it about the wall. Good option in the event you are seeking a little something additional portable. It follows the https://allhealthmarket.com/product/home-care-2/oxygen-and-hydrogen-generator/hydrogen-inhalation-machine-300ml-450ml-inhalation-machine-molecular-oxygen-hydrogen-generator-h2-inhaler-water-ionizer-spe-pem/