2-Layer thermal liner - shoulder length design keeps head, ears and neck warm and covered. Flame-resistant outer shell - 60% Modacrylic/40% cotton twill blend. Flame-resistant lining - 60% Modacrylic/40% cotton fleece blend. Tested and approved- meets requirements of performance specification ASTM F1506; classified CAT2 according to NFPA 70E, arc-rated; ATPV rating of 17 cal/cm2. Zip-off cap - versatile design with a zipper to separate top and lower parts, as well as a button to lift sides to vent heat. Lightweight - fits comfortably under a helmet or hard hat without feeling too bulky. Elastic fit - elastic gather at forehead closes the gap between liner and forehead to keep the heat in and cold out. Hook and loop straps- 4 evenly spaced straps included on the outside of the liner to attach to hard hat or helmet suspension. Optional warming packs- pockets by ears to hold hand warmers (sold separately). N-Ferno Black Modacrylic/Cotton Blend/Polyester Winter Liner | 16885