These masks are made from 3 layers of cloth. The outer and inner layer are made from 100% cotton and the middle layer is a filter. The soft T-shirt yarn can be used to tie behind the head or ears and is much comfier than elastic (it also does not melt when ironing your mask ;))
There is a moldable nose bridge if ordered in an Adult size (a coated wire has been sewn into the top) to make sure it fits snugly on your face and limits air between face and mask.