... uses the electronic theory to produce the negative ions and Ozone.* Negative ions are initiated from the electric ... gastritis, upper respiratory tract inflammation, bronchial asthma, atrophic rhinitis, and stomatitis* Portable, easy to carry.Adaptation range*Trains, airplanes, ... area, most suitable for allergic people with asthma and pregnant women. Negative ion air purifier/ozon generator (Sy2083)