The prototype was the M-51 multi-bag field pants in the early Korean War, which was used in conjunction with the field jacket. Because it can be used outside the wool combat trousers, but also has a matching liner, the pants are large, and it is a field pants that is launched in response to extreme cold weather. The fabric is finished with a new version of thick cotton satin, which is thicker than all previous versions. The trousers are loose, cut in the next year, the trousers are slightly reduced, and the upper body is comfortable. The side pocket drawstring is used to tie the side pockets to prevent bumps. The drawstring can also be shrunk into the pocket. The trousers also have a drawstring to reduce the size of the foot.