Wearable Necklace Air Purifier Mini Portable Negative Ion Generator Low Noise Features: *1.Portable mini air purifier comes with a durable lanyard, can be hung around the neck like wearing a delicate necklace, easy to carry without any burden. *2.It is USB charging, low power consumption, zero ozone, no radiation, safer and healthier to use. *3.The negative ion generator can effectively absorb formaldehyde, it can can release up to 19.99 million negative ions to resolve the air quality problems around you, like eliminate second-hand             smoke and purify the surrounding air. *4.Easy to operate, one button for on/off.Just press the button for two seconds to enjoy the fresh air. *5.The air purifier's working volume is as low as 30db, so you can use it in the office or bedroom without any disturb. Specifications: Material: PC Negative ion concentration: 19.99 million pcs / cm³ Input voltage: 5V Input power: 0.1W Charging time:about 1 hour Length of use:15~21 hours Power Supply:USB battery capacity:200MAH Color: Black/White Package included : 1 * Negative ion purifier 1 * USB charging cable 1 * Lanyard 1 * Use manual