One thing about the American forces during World War II: they had our not-quite-as-globalized companies behind them, a fact that these corporations now like to highlight.
Today, GE posted about their Copper Man, a dummy with a thin copper skin, which was used to test the heated flight suits that kept our men in the bombers warm until pressurized cabins of the B-29.
The suits worked like electric blankets—wires running in-between layers of wool—and as the engineers worked to optimize the suit, they would try it out in a cold room in Fort Monmouth, New Jersey. While human volunteers also participated in the experiments, the Copper Man had an electrical mesh on its "head, hands, torso, and feet" through which researchers could take readings on how the suit was performing.
After the suits became unnecessary, GE took the technology and found a way to sell it to consumers in a postwar world: actual electric blankets.