Jeep cap

The jeep cap originally the US Army issued M1941 wool knit cap (Cap, Wool, Knit, M1941) is generally like a toboggan cap (or some sources also describe it as a beanie) with a short, baseball cap-like brim attached to it, made mostly from knitted yarn, originally wool but now more often acrylic. Also sometimes referred to as a "skull cap" due to its popularity with skateboarders (although the term "" is also used for a variety of completely different caps), or a "Radar cap" due to the cap being made famous by the character Radar O'Reilly from the hit US TV sitcom M*A*S*H.

The "jeep cap" was first issued by the United States Army in February 1942 during World War II; the purpose of the jeep cap was to be worn underneath the heavy combat helmets to offer soldiers both extra padding, and warmth. The jeep cap was originally knitted close to the head, with a six-stitch "starfish pattern" on top (supposedly to support the webbing suspension inside the helmets), with a cuff coming out like a V from the top center of the brim, and around the rest of the cap, which soldiers could pull down over their ears for even more warmth. The cap was issued in four different sizes – small, medium, large, and extra large – and made of olive drab (O.D. #3) wool; perfect examples of these original jeep caps can be found being worn by Staff Sergeant Kinchloe from the sitcom Hogan's Heroes (he wore his with the brim folded up), and Radar O'Reilly from M*A*S*H (who was seldom seen without one). Another great example of characters depicted wearing the cap is the classic WW2 movie Stalag 17. Although made specifically for wear under the steel pot helmet, the cap alone grew to be very popular with soldiers for its casual and relaxed look, and was often worn on its own. The cap was usually only issued to enlisted men, however, officers (General Patton in particular) despised the cap for its "slovenly" and "un-military" look, and it was eventually phased out and replaced with the standardized field cap, as part of the newer, layered U.S. Army M-1943 Uniform.

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Wikipedia