Our Airtamer A302 Travel Air Purifier features: -State-of-the-art electrostatic purification cleans the air more than 10 times better than other travel air purifiers, as much as 439 cu ft per hour! -No filters to buy, clean or replace -It's silent and attractive design can be discreetly worn using its safe breakaway lanyard or integrated clip -This unit offers more than 180 hours of continuous runtime and can be stored in it's included metal travel case when not in use