The N-Ferno 6893ZI Zippered Balaclava Face Mask with Bump Cap Insert provides warmth for extreme cold, as well as lightweight protection from bumps, scrapes, bruises and other minor head injuries. Wear alone as a balaclava face mask or open the top zippered compartment to add the Skullerz 8945 Universal Bump Cap Insert (included) for work in cramped spaces. Also compatible with Skullerz 8945F(x) Universal Bump Cap Insert with Extra Venting and Skullerz 8943F(x) Hinged Universal Bum