2.mask pm shipmask dhl pad ply breathable filter pm2.5 5 paper for haze face mask activated carbon anti dust mouth er ou

5 ply famask pad breathable pm 2.5 paper for anti haze dust famask activated carbon anti dust mouth er outdoor w.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.