Vintage.es shows a silly invention from 1941. It’s a phosphorescent mitten to make your hand signals more visible to following drivers.
Might have made sense in the ’20s, but by ’41 many car brands offered optional turn signals. The demonstration is especially silly because it’s a ’41 BUICK, which made turn signals STANDARD in ’38. So a Buick was the one car among all brands that couldn’t possibly need this invention.
Polistra's Mill 