The Hot Shield has the latest in extreme thermal resistant fiber technology. They are made of CarbonX fabric. This new fabric is nonflammable, and will not shrink, crack or char when exposed to temperatures exceeding 2000 degrees F. The Hot Shield protector has an internal pocket that allows you to insert any particulate mask of your choice (2 included). This increases the level of filtration and protection from particulates. For added comfort, there is an extra layer of super soft CarbonX at the bridge of the nose. One size fits all. Black only.