The N-Ferno 6870 Thermal Mouthpiece has two layers of insulation with a cotton shell and a polyester fleece liner to provide comfort, warmth and face protection in extremely cold weather work conditions. This thermal winter face mask is made to fit most N-Ferno Winter Liners (sold separately) to double up the warmth on those frigid jobsites. The shell design prevents the mask from being sucked into the mouth for plenty of breathing space and protection from the cold air. The detachable face mask allows you to let in air or remove for speaking when needed. The adjustable hook and loop closure have a secure and adjustable fit to prevent the mask from moving around during any task. Great cold weather work gear for people who spend extended periods of time in cold environments such as construction, freight, drilling or mining, delivery service, landscaping, and warehousing.