Prior to the start of the war, troops were issued wool blankets depending on the climate they would be sleeping in. At least one was given and as many as needed (and available) to keep warm. However, once America became involved in the conflict overseas, logistics became a problem. Troops were stuck with their one issue and had to scrounge for more to stay warm.
The wool blanket hadn't changed much since World War I, save for color. Proper WW2 blankets are going to appear a darker OD, almost matching the serge material of the dress uniforms. Of course, there is a lot variation from maker to maker, and you can expect to find blankets greener than others.
Blankets are easy to find and can often be bought at your local surplus store. We recommend you buy one, and two or more if you plan to do a lot of camping events. At least one blanket is needed as it will help round out your haversack when you strap it in.
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