High efficiency air filter for air purifier part 1. ISO, RoHS, SGS 2. high efficiency, ... has the function to purify and absorb the odor substances, for example, ammonia, fluorine, formaldehyde, methanthiol, hydrogen sulfide etc, but also ... function: absorb and kill the bacteria2).Long residual action: No effect change for the fabric with nano silver being washed 1000 times3 ...