5 pm2.filter protective layer pm2.5 mask activated filter carbon gasket safe anti dust breathable famask replacement pad k877

5 layer mask protective pm2.5 activated carbon gasket safe anti dust breathable famask replacement pad k877.1.the first layer: high efficient filter cloth filter the dust of micron.2.the second layer: meltblown cloth to filter industrial pollutants, automobile exhaust, second-hand smoke pollen allergies.3.the third layer: high efficient filter cloth filter benzene and a smaller function of filtering dust microns.4.the fourth layer: activated carbon cloth filter density, sma.