dhl shippm2.5 activated carbon protective pm2.5 pad mouth faer insert replaceable anti-haze fashield s pads

pm2.5 replaceable s activated carbon protective mouth faer insert replaceable s anti-haze fashield s pads 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.