... harmless, no sensitive reaction. Application:1). Central air conditioner, air HFPA purifier, air cleaner, Fragrance machine etc.2). Medical nano silver ... Our filters is widely used on air purifier, cleaner, humidifcation appliance and air conditionner etc. Welcome to contact us ... Our filters is widely used on air purifier, cleaner, humidifcation appliance and air conditionner etc. Welcome to contact us ...