Mini Air Purifier Compared with other air purifiers, this USB plug-in air purifier is small in size and allows you to travel easily. Negative ion purification function: The air ion generator generates negative ions, which are combined with the dust of positive ions in the air and sink to the ground to avoid the danger of inhaling floating objects. And to achieve the removal of cigarette smoke, oil fume and other particulate matter. Effectively freshen the air and improve the quality of sleep. Low noise, environmental protection and health: This filterless air purifier allows you to work immediately without replacing expensive accessories, just plug it. Release 20 million negative ions, so that harmful dust carried by positive ions in the air loses vitality. Easy to use, plug and play. Product name: USB air purifier Negative ion concentration: 20 million pcs/cm Power plug type: USB Working principle: negative ion Noise: 36 (dB) Air volume of air purifier: 301-400 cubic meters/hour Applicable area: 31 (inclusive)-40 (inclusive) Material:ABS+metal "all Products From Us Have Undergone Strict Quality Checks. if There Is Any Quality Problem Or You Are Not Satisfied With The Product contact Us. we Will Give You The Best Solution."