1、Neagative ions can effectively purify air, remove PM2.5, dust, smog, formaldehyde, harmful substances etc. 2、One time full charge can last for more than 30 hours at high-end mode, more than 60 hours at low-end mode. 3、Red light on while charging, blue light on while it is full charged or it is working. Please power off while charging the purifier. 4、Low-end mode the negative ion concentration is 8000W/m³, high-end mode the negative ion concentration is 12000W/m³. 5、The working sound is very quiet, you can wear it and enjoy fresh air everywhere. 6、Lightweight, compact and portable, the necklace ion air purifier have no radiation for kids and adults. 7、First press the power on/off button for low-end mode, second press for high-end mode, third press the power is off. 8、Suitable for kids, the elders, pregnant women and people who are allergic to pollen and odor, effectively protect those who are suceptible to air pollution. 9、Suitable for all ages and all occasions to wear. Energy-saving and time-saving product, take good care of your health. 10、Made of ABS and food-grade 304 stainless steel, environmental-friendly, strong and not easy to break, no need to replace the negative-ion generator. 11、Exquisite appearance, smart display, beautiful design and convenient to use. Features: Neagative ions can effectively purify air, remove PM2.5, dust, smog, formaldehyde, harmful substances etc. One time full charge can last for more than 30 hours at high-end mode, more than 60 hours at low-end mode. Red light on while charging, blue light on while it is full charged or it is working. Please power off while charging the purifier. Low-end mode the negative ion concentration is 8000W/m³, high-end mode the negative ion concentration is 12000W/m³. The working sound is very quiet, you can wear it and enjoy fresh air everywhere. Lightweight, compact and portable, the necklace ion air purifier have no radiation for kids and adults. First press the power on/off button for low-end mode, second press for high-end mode, third press the power is off. Suitable for kids, the elders, pregnant women and people who are allergic to pollen and odor, effectively protect those who are suceptible to air pollution. Suitable for all ages and all occasions to wear. Energy-saving and time-saving product, take good care of your health. Made of ABS and food-grade 304 stainless steel, environmental-friendly, strong and not easy to break, no need to replace the negative-ion generator. Exquisite appearance, smart display, beautiful design and convenient to use. Specifications: Type: Negative Ion Battery: 3.7V Lithium Battery Anion Concentration: 8000-12000W/cm³ Rated Frequency: 50 (HZ) Application area: ＜10㎡ Air Volume: 51-150m³/h Noise: 20dB Power Supply: USB Rated Power: ＜1W Current: ＜40 mA Battery Capacity: 700mA Material: ABS, Stainless Steel Color: Black, White(optional) Weight: 153g/5.4oz Size: 15*9.5*3cm/5.9*3.7*1.2in Package List: 1*Necklace Purifier 1*USB Cable 1*Necklace Purifier 1*USB Cable