The N-Ferno 6874 Thermal Mouthpiece has two layers of insulation with a neoprene shell and a 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 extra-frigid jobsites. The water-resistant, 1 mm neoprene is warm and breathable while remaining soft and stretchy for a close, heat-trapping fit. Polyester fleece lines the inside of the mouthpiece for comfort against the skin, long wear and optimal breathability. 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.