I have seen these jackets-the inside lining has a material which is covered with metallic dots. The idea is that the dots reflect the wearer’s body heat back to him-keeping the wearer warm. It sounds reasonable, but does it actually work?
NASA and the US military seem to think so.
Moved Cafe Society --> IMHO.
Extensive user reviewhere
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It’s called Omni-Heat Reflective and, yes, it does work, in the same way a reflective blanket works. The dots design allows for breathability (between the dots) rather than just having a full sheet reflective material. That’s pretty important feature in technical clothing designed for cold-weather activities that generate body heat and perspiration. It also allows for greater comfort for fabric that lies directly next to the skin, including Omni-Heat Reflective base layers, hats, gloves and neck gaiters.