The U.S. Army developed the M1943 uniform manufactured in herringbone twill (HBT) cloth beginning in 1942 to replace a variety of other specialist uniforms and some inadequate garments, like the M1941 Field Jacket.
By 1941, soldiers wore a wool flannel shirt and wool serge trousers in winter and a cotton khaki shirt and trousers in summer, both with ankle-length russet leather service shoes and OD canvas leggings, and often with the OD cotton M1941 Field Jacket. A blue denim fatigue uniform was gradually being replaced by a M1941 green HBT uniform; both were in two pieces.
Armored units still were using wool riding breeches and wore high-lacing boots in some cases, and the Paratroopers were stuck with a general issue HBT overalls with no real suitable footwear.
As a result of this lack of proper and suitable clothing, the Armored units were issued general infantry uniforms, although by 1942 the winter coveralls and winter "tanker" jacket had been produced with them in mind. These articles of clothing were made of light green cotton lined with wool kersey.
The paratroopers got their own unique uniform in 1942, also. It was constructed of light green cotton twill, with four front pockets and two pant-leg cargo pockets. They also got a new boot design of their own, a leather boot of similar construction to the infantry shoe, only being mid-shin high.
Generally speaking though, this was unsatisfactory. The infantry uniform was lacking in functionality compared to the M-1942 Paratrooper uniform, and the tanker winter uniforms were sought after by almost every branch in the Army, making supply and production often difficult.
The combat wool, khaki, and paratrooper trousers all did not have adequate locking stitches in the crotch. Often trousers would tear at that stress point. Also, the paratrooper uniform would tear at the knees and elbows. The paratroopers tried to fix the problem by sewing canvas patches on the elbows and knees, but the Army sought to standardize a better uniform.
The most recognizable part of the uniform is the standardized field jacket. It was longer than the M-1941 jacket, coming down to the upper thighs. It was made in a light olive-drab OD7, later a darker OD9 cotton sateen. It also had a detachable hood, drawstring waist, two large breast pockets and two skirt pockets.
The trousers were made out of the same cotton sateen material and regular cotton twill. They were made similarly to the khaki trousers, with better design features. They also had buttoned tabs at the waist in order to cinch the waist in.