valve reusable anti-dust breathing mask with fabric washable mouth face pm2.5 pad in stock

reusable fabric pm2.5 mouth mask anti-dust mask reusable mask with breathing valve washable mouth face pad in stock features: 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.