dhl shipwholesale filter pads 5 layers protective dustproof replacement insert pm2.5 activate carbon mask

wholesale mask pads 5 layers protective pm2.5 dustproof mask replacement insert pads breathable fy6014 9.1.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.