Our Airtamer A302 Personal / Compact / Travel Air Purifier features: -Wear AirTamer to create a cleaner zone of healthier air while traveling, in public spaces or in other poor air quality locations. -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 Dimensions: 3" x 1" x 1.25" SPECIFICATIONS: Two lithium coin cell batteries are included with AirTamer, providing up to seven days of continual power; AirTamer A302 dimensions 3" x 1" x 1.25"; Includes proprietary conductive lanyard which is adjustable and features a break-away connector for extra safety.