ARLINGTON, Va. — The Army has tweaked the fire-resistant long-sleeve pullover shirt under development for troops to wear under body armor, replacing the fabric in the torso for material that is lighter and more breathable, officials announced this week.

The new fabric in the flame-resistant Army Combat Shirt “provides breathability that is off the charts,” Maj. Clay Williamson, assistant product manager for clothing and individual equipment at the Army’s Program Executive Office Soldier at Fort Belvoir, Va., said in a news release about changes to the shirt.

PEO Soldier began developing the Army Combat Shirt, or ACS, last year to give soldiers an extra layer of protection against fires caused by roadside bombs or rocket-propelled grenades.

Developers began field-testing shirts with soldiers this spring, and the changes are the results of their feedback, Williamson said.

The shirts, which have a solid-green torso and sleeves printed in a universal camouflage pattern that matches the Army Combat Uniform, or ACU, are supposed to be worn under body armor. The mock-turtleneck pullovers are made of anti-microbial, moisture-wicking, fire-resistant cotton and rayon blend fabric.

Soldiers who wore the garments “wanted it to be even more breathable and comfortable,” Williamson said in the release.

In addition to swapping fabrics, developers replaced elastic cuffs — designed to keep out sand — with adjustable cuffs that soldiers can loosen for ventilation, similar to ACU jacket cuffs, Williamson said.

The new versions will also have hook-and-loop tape on the left and right sleeves, to accommodate name and rank tapes and unit patches. The original version of the shirt already included hook-and-loop fasteners for American flag shoulder patches.

The ACS with the most recent improvements will be available in late September for follow-on user evaluations, Williamson said. But since the shirt “is still a developmental garment,” the Army still doesn’t have a schedule for force-wide distribution, the release said.

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