5 Layer KN95 dustproof face masks. Must be ordered in sets of 50. CDC recommends face coverings to prevent the spread of coronavirus / COVID-19. KN95 masks provide 95% filtering of non-oil based and aerosol particulates greater than 3 microns. Each mask is produced with 3 layers of professional grade non-woven polypropylene and 2 layers of melt-blown microfiber fabric for efficient filtering. The no-valve design has a high filtering and vacuum sealing effect to provide more protection. 4" W x 4" H
