STEEL STANDING face masks are Superior-Quality, 4-layer protective masks. The first three layers consist of two layers of anti-bacterial fabric with one non-woven anti-microbial filter in between that can be machine washed 50 times. The fourth layer simultaneously serves as a sleeve where one can insert their own filter for another layer of protection and for continued use. All masks come standard equipped with non-tarnishing metal alloy cord locks which can easily adjust the mask to comfortably accommodate any adult size face.