Lightweight thermal liner is shoulder-length to keep head, ears, and neck covered, and fits comfortably under helmets or hard hats without feeling too bulky Four hook & loop straps on the exterior of the liner securely attach to the interior of a hard hat Features pockets by the ears designed to hold regular-sized hand warmers (sold separately) to keep ears warm and comfortable in extreme temperatures Both the liner and mouthpiece have a fire-resistant outer shell and lining made of 60% modacrylic cotton and 40% cotton twill blend to stand up to tough environments and meets requirements of performance specification ASTM F1506 Elastic strip in the forehead area keeps the liner snug against the face to trap body heat in and keep cold out Detachable face mask design allows you to let in air or remove for speaking when needed Hook and loop closures on the mouthpiece have a secure and adjustable fit to prevent the mask from moving around Hard-shell design of the mask prevents it from being sucked into the mouth to allow plenty of breathing space Machine washable Arc-rated Colour Black Material Cotton/Modacrylic Standards Met ASTM F1506
