dhl shipk mask insert dustproof kid pad inner replacement antidust pm2.5 5 layers soft breathable ation pads

k mask pads insert dustproof inner replacement antidust pm2.5 5 layers soft breathable ation pads r.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.