Why we need a HEPA air purifier?

HEPA air purifier is a common tool used in many mechanical air cleaner to filter small, unwanted, and unhealthy particles out of the air.
HEPA air purifier can effectively remove pm2.5 Pollution hazard, slew rate up to 95%.

You can use it at home or office or have easy carry one put in car, let good air comes along with you.