dhl ship1000 1 pcs replacement fliter activated carbon insert 5 layers pm2.5 pad protective mask inner pads breathable

1000 1 pcs mask replacement fliter activated carbon insert 5 layers protective mask inner pads breathable m.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.