layer earring dust pm2.5 activate carbon filter mouth mask ered with 3 layers of 4bla

mask 3 layer earring dust mask ered with 3 layers of non-woven cloth dust mask soft breathable outdoor pad pm2.5 b11.1.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.