dhl shippm2.5 face mouth pm2.5 pad gasket 5 layer mask pads mat

pm2.5 famouth mask gasket 5 layer mask pads mat 0.1.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.