Introducing a product that is safe and reliable in Japan. Negative ions from Airvida catch pollen and dust floating in the air, improving your air environment. PM2.5 removal rate 99.9 %, formaldehyde removal rate 99.9 %, bacteria removal rate 96.8 %; Effective for dust mites death, foul, pet hair, and cigarette smoke. Easy to charge via USB. So you can use it anytime, anywhere. Negative ions from Airvida are 1.23 million pieces?Its number is about 60 times the surrounding waterfall in the forest! Great for home or office, as well as for commuting to work or school, restaurants, concert venues, and other places where people gather together.