 We couldn't wear them because they weren't uniform. If you can tuck it under something and hide it without there being a bulge, I suppose you could get away with it. But the other thing, too, is that your primary cooling is your own sweat, your own internal system. And so while those may be effective, again, I never actually used one. I might even still have some. My cooling system works actually relatively well, and so I don't.