dhl ship1 1 pcs air fiters haze and dustproof mask pad pm2.5 breathable replaceable filte hot

1 1 pcs air mask fiters haze and dustproof mask pad pm2.5 breathable replaceable filte 7.1.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.