Buy 200 masks + get 300 as a random gift. How many masks are they?

500. A mask is a sanitary and anti-epidemic product. It is generally worn on the mouth and nose to filter the air entering the mouth and nose to block harmful gases, odors, droplets, viruses and other substances. It is made of gauze or paper and other materials. . Masks have a certain filtering effect on the air entering the lungs. Wearing masks has a very good effect when respiratory infectious diseases are prevalent and when working in dust and other polluted environments. Masks can be divided into air filter masks and air supply masks.