dustproof pm2.5 pad adjustable include earloop mask original anti smoke 5 layer pm2.529j9

pm2.5 adjustable earloop mask include pad dustproof anti smoke reusable cotton protective famask for cycling running outdoor 5.1.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.