These masks have charcoal inside the material.
The masks are polyester, carbon-activated, anti-microbial, washable, reusable, breathable and have 2 adjustable elastic straps in the back and two cord locks to create the custom fit. . One strap goes around the neck and the other one goes around the middle of the head. Dimensions are 7 1/2" from ear to ear and 5 3/4" from nose to chin.