TK4 Tourniquet. For men and women in combat environments, immediate first aid can be the difference between life and death. Severe injuries in inaccessible areas creates the need for immediate trauma care. The H&H TK-4 tourniquet is designed specifically for this purpose. Its one-handed application provides a simple to use device that makes stopping arterial bleeding easy and direct for injuries ranging from combat trauma to accidental amputation. TK-4 features a newly developed woven elastic textile band (3” wide by 40” long) that provides incredible strength and flexibility. With two steel hooks fastened steadfast (three thick hog rings per S-Hook) to both ends of the elastic band, and packaged in a small, vacuum-sealed pouch. TK-4 is the perfect solution for any kind of injury involving arterial bleeding. TK-4 has been deployed by the US Marine Corps, US Special Forces, and numerous law enforcement and emergency services.