Extended Cold Weather Clothing System The Extended Cold Weather Clothing System ( ECWCS ; ) 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 ) Components . The entire ECWCS ensemble ( 1st generation ) consists of polypropylene ( 1 ) undershirt and ( 2 ) underwear [ drawers ] , polyester fiberpile ( 3 ) shirt and ( 4 ) bib , ( 5 ) nylon / cotton trousers , Brookwood Assault or Gore - Tex ( 6 ) parka and ( 7 ) trousers , liners for the ( 8 ) parka and ( 9 ) trousers , ( 10 ) white ( snow camouflage ) parka / trousers cover , ( 11 ) gloves , ( 12 ) glove inserts , ( 13 ) mittens , ( 14 ) mitten inserts , ( 15 ) mitten shells , ( 16 ) white mitten shells ( snow camouflage ) , ( 17 ) cap , ( 18 ) balaclava , ( 19 ) nylon socks , boots — both ( 20 ) cold weather vapor barrier boots and ( 21 ) extreme cold weather vapor barrier boots — and ( 22 ) M - 1950 trouser suspenders . 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 the Brookwood Assault or 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 breathable Brookwood Assault or 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 with Brookwood Assault Seam Tape or Gore - Seam tape . The ECWCS parka . The parka — which is a particularly popular component — is characterized by a cobra hood ( which fits over a combat helmet ) with woven nylon drawstring adjustable pulls and an attachment piece that allows fastening of a fur ruff ( early models of the parka lacked this attachment piece ) . There is a two - way , full - front slide fastener to provide full - face protection , leaving only the eyes uncovered . The parka has Raglan shoulders / sleeves , a non - freezing , double - pull zipper with storm flap and seven snap closure , a flap - covered pocket on the left sleeve with hook and loop ( Velcro ) closure , adjustable hook and loop wrist cuffs , armpit ventilation zippers and double reinforced elbows . A badge / insignia tab with snap is located on the storm flap . There is an interior back ventilation opening , two slash ( handwarmer ) cargo pocket s on the lower front ( with extra large flaps and double hook and loop single snap closure on each ) and an inside draft skirt ( windskirt ) with elastic drawcord s and barrel - lock s at the waist ( without pulls ) . There are also two concealed map pockets at the front zipper with hook and loop closures that can be opened without unzipping the parka . 2nd Generation . The second generation ( 2G ) ECWCS includes two different layers made with Polartec fabrics : the Polartec Classic 300 shirt and the Polartec Classic 200 overalls . When used in combination with other layers in the ECWCS system , the system provides protection between + 40 °F and −40 °F ( + 4 °C and −40 °C ) . 2G ECWCS is currently being worn by US Special Forces , US Army and US Air Force soldiers stationed in extreme environments from Norway and Bosnia to Afghanistan . 3rd Generation . The third generation 3G or GEN III Extended Climate Warfighter Clothing System is a radical re - design of the system . It features seven new layers of insulation including three Polartec fabrics : two layers of Polartec Power Dry and a layer of Polartec Thermal Pro High Loft . The 12 components of the GEN III ECWCS include a lightweight undershirt and drawers , midweight shirt and drawers , fleece cold weather jacket , wind cold weather jacket , soft shell jacket and trousers , extreme cold / wet weather jacket and trousers , extreme cold weather parka and trousers . Initial fielding of the system began in August 2007 to the 73rd Cavalry Regiment in Afghanistan .