Ready-Heat Disposable Heated Blankets use proprietary panel technology are used for slow continuous and consistent warming. They heat up gradually over a period of 15-30 minutes and after reaching peak temperature will remain warm for 8 hours. The Ready-Heat blankets are used to aid in the treatment of hypothermia, shock and patient trauma. Due to their high tensile strength both can be used as an evacuation litter (if needed) and can carry a person weighing up to 250 lbs. Both blankets are US Military protocol used in the transport of wounded soldiers and the Ready-Heat 4 panel (torso size) is carried by every US Army Medic. All Ready-Heat Blankets using panel technology come individually sealed in an oxygen free protective poly-bag. When the poly-bag is opened, the blanket's heating elements react with the oxygen in the atmosphere and generate heat. The heat generated will provide sufficient warmth and comfort to the user for up to 8 hours. All Ready-Heat Blankets have been approved for use on fixed wing and rotary aircraft by the US Military.