A face mask is a sanitary product, generally refers to a device worn on the nose and nose to filter the air entering the nose and nose to prevent harmful gases, odors, and droplets from entering and exiting the wearer's nose and nose, and is made of gauze or paper.
Masks have a certain filtering effect on the air entering the lungs. When respiratory infections are prevalent, wearing masks has a very good effect when working in a polluted environment such as dust.
Masks can be divided into air filter masks and air supply masks.

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