The N-Ferno 6850 Winter Hard Hat Liner has 2 layers of insulation with a cotton shell and a comfortable polyester fleece lining for exceptional warmth. This lightweight thermal liner is chin-length to keep head and ears covered and fits comfortably under helmets or hard hats without feeling too bulky. The outer shell is made with 100% cotton twill to stand up to tough environments. The 100% polyester fleece lining is soft to the touch for comfortable all-day wear. A hook & loo