These disposables are made of 2 layers of shop towel and an inner layer of nonwoven tissue.
Disposables (25 per pack)
Initiative Info and Printable Catalog
Not lab tested, but meant as an emergency mask for one time, short term use. Read an article about the materials used: https://totallythebomb.com/blue-shop-towels-may-be-the-best-material-to-use-when-making-face-masks?fbclid=IwAR0URoaEU0uCBF7Jn30gEXe9HB64Yq-_E6SxZfWXwmyMd7g9IutfeMh9afE