Product name: hanging neck air purifier Product model: portable air purifier Product size: 53*13mm Main function: Fashionable new product can wear negative ion air purifier, rechargeable, charge for two hours and use for 30 hours. The product has a built-in high-concentration negative ion generator, which can effectively purify harmful substances in the air, kill bacteria, remove formaldehyde, peculiar smell, and second-hand smoke