Summary

Joint Task Force Guantanamo Department of Defense correspondence regarding contraband underwear at Guantanamo Bay (2007)

I don't mean to say that it is an open and shut case proving that your military provided the underwear, as 1 understand that other people use Under Armour. One group I noticed on the web were the amateur weight lifters, who seem confused as to whether Under Armour give them a competitive advantage.
Source: Wikisource

Joint Task Force Guantanamo Department of Defense correspondence regarding contraband underwear at Guantanamo Bay (2007)

There is clearly a need for a better alternative than the standard-issue cotton T-shirt."
There must be other clues as to the provenance of these underpants. Perhaps you might check the label to see whether these are tactical' underwear, as this is apparently something Under Armour has created specially for the military: Under Armour has a line of apparel called Tactical that's modified for soldiers. It features the same styles as civilian tops and bottoms - LooseGear for all purpose conditions. HeatGear and ColdGear, meant for hot and cold weather, as well as a line for women.
Source: Wikisource

Joint Task Force Guantanamo Department of Defense correspondence regarding contraband underwear at Guantanamo Bay (2007)

Sometimes I have to go long times in hot weather without showers. Under Armour prevents some of the nasty side effects of these extreme conditions. All of my buddies out here use the same thing. They're soldier-essential equipment. The only thing that would make them better is if the Army would issue them.
Source: Wikisource

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