To protect your head and neck from the elements, the 6892 FR 3-Layer Hard Hat Liner has three layers of insulation and flame-resistant protection: twill shell, foam mid-layer and modacrylic/cotton lining. Shoulder-length shell and lining are made with 60 percent modacrylic and 40 percent cotton twill for ultimate protection from cold-related and fire-related injuries. Mid-layer lining fits comfortably under hard hats without bulking. Foam insulation provides an additional layer of thermal protection. Hook-and-loop closure creates a customizable fit. Attach four exterior, hook-and-loop closures to the interior of a hard hat for extra security and warmth. Elastic strip on forehead keeps the liner snug against the face to trap body heat in. Small pockets by ears hold regular-size hand warmers (not included). For extra face coverage, attach N-Ferno 6870, 6872 or 6874 mouth covers (not included). Liner is perfect for workers in construction, drilling/mining and more.