6876 FR Hard Hat Liner with FR Mouth Cover Kit keeps workers warm in cold environments with its full-face and neck, flame-resistant coverage. This kit meets ASTM F1506 and NFPA 70E for ARC flash prevention. Made with two layers of insulation, 60 percent modacrylic and 40 percent cotton twill, this liner protects you from harsh conditions and flame-related injuries. Shell design prevents mouth cover from being sucked into the mouth for plenty of breathing space and protection from the cold air. Easily remove detachable mouth cover when needing air or to talk. Liner fits comfortably under hard hats without adding too much bulk. Hook-and-loop closure has a secure fit to prevent the cover from moving around during any task. Attach four exterior, hook-and-loop closures to the interior of a hard hat for extra security and warmth. Elastic strip on the forehead area keeps the liner snug against the face to trap body heat and keeps cold out.