Features: 1.Using pulsed tip technology to release a large amount of oxygen anions, using the latest dual carbon brush and double negative ion generator design, over 20 million negative ions can effectively remove floating dust, smoke, formaldehyde, PM2.5 and other harmful substances in the air. 2. Release a large amount of oxygen anions, kill harmful bacteria, molds , decompose fumes, odors, and harmful gases such as formaldehyde and benzene released by car interior parts (such as plates and leather). 3. Negative ions promote metabolism, activate cells, refreshing and relieve motion sickness. Technical Parameters: Use voltage: DC5V Power: Negative ion concentration: 20 million pcs \/ cm3 Product weight: 30g Weight including packaging accessories: 113g Product size: 55 * 16mm Life time: 48 hours Packing size: 10 * 10 * 3.2 cm Packaging accessories: Stainless steel necklace * 1 Manual in Chinese and English * 1 USB charging cable * 1 Negative ion purifier * 1