Extended Cold Weather Clothing System

The Extended Cold Weather Clothing System (ECWCS; /ˈɛkwæks/ EK-waks) is a protective clothing system developed in the 1980s by the United States Army Natick Soldier Research, Development and Engineering Center, Natick, Massachusetts. The first generation ECWCS consisted of parka and trousers plus 20 other individual clothing, handwear, headwear and footwear items which are used in various combinations to meet the cold weather environmental requirements of the US military (and others). The Gen III ECWCS is designed to maintain adequate environmental protection in temperatures ranging between -60 and +40 Fahrenheit (about -51 and +4 Celsius)

The entire ECWCS ensemble (1st generation) consists of:

The system is to be used in an insulated, triple-layering fashion, with the polypropylene undergarments as Layer 1, the polyester shirt/bib, liners and cotton/nylon trousers as Layer 2, and Gore-Tex outer garments as Layer 3.

The parka and trousers (which have been adapted to the civilian outdoor clothing market) are themselves constructed in a three-layer fashion consisting of an outer layer of abrasion-resistant taslan nylon, an intermediate layer of durably waterproof, windproof, and Gore-Tex membrane (protected with a layer of nylon tricot and originally in a four-color camouflage print), and a hung inner layer of unlaminated nylon. The whole is seam-sealed.

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