In 1938 the U.S. Army introduced cotton HBT (herringbone twill) for summer weight coveralls. In 1941 the former blue denim summer work uniform was replaced by a new light shade olive drab HBT uniform consisting of a jacket-style shirt and trousers (top photo on this page). The HBT uniform was originally intended to be only for work duty but quickly became the standard dress for all types of informal temperate weather activity, including combat, replacing the cotton khaki uniform. It was also used as an outer layer over wool shirt and trousers in very cold weather locations where more layers were needed.
HBT cloth and 13 star button.
Jacket, Herringbone Twill
The popular uniform jacket-shirt was made in several styles. The original 1941 pattern jacket (PQD 45) had a button front with lapels, two pleated breast pockets with angle-cut flaps, and adjustments by straps at the waist and buttons on the sleeves. Metal buttons with 13 stars and black paint were used, although plastic buttons for use in hot weather or inside armored vehicles were also issued. It can be identified by two closely spaced buttons at the sewn double hem.
In 1942 another pattern HBT jacket was introduced (PQD 45B), featuring square cut cargo pockets, side pleats, and a plain hem with only one button near the bottom. A further modififation was the Special version of the same jacket (PQD 45C) with the addition of a gas flap and buttons at the back of the collar to attach a gas hood. Finally, in 1943, another pattern (PQD 45D) was the same as PQD 45C but made in the darker shade of OD called OD #7, mostly issued in 1944 or later. The 1942 pattern and its later variations are the most common, having been used in Europe and the Pacific for all types of service.
The size of these jackets was much larger than the size tag that was sewn into the inside collar. They were meant to be worn over other layers of clothing -- for example, the wool shirt could be worn under the HBT jacket for extra warmth in cold weather. If you picked the jacket for your normal size, and wore it alone, you were swimming in it.
Herringbone Twill Combat Fatigue Trousers
For each of the HBT jackets there is a corresponding pattern of the "Trousers, Herringbone Twill". The first, in 1941 (PQD 42), matched the jacket in the style of pocket and metal buttons. The second (PQD 42A) had cargo pockets with square cut flaps, like the 45B jacket, and a gas flap. With the gas flap, Special was added to the nomenclature. Spec PQD 45C came in 1943 with the only change being the color, now the darker OD #7.
To the right is a photo of a Marine Corps enlistee in his fatigue uniform, taken at Camp Lejeune in New River, NC, March 1943. Even though he is in the USMC, the jacket appears to be a US Army HBT jacket, in the 1941 pattern, and not the USMC fatigues you would expect.
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