This Christian Science Monitor article mentions a technology that I hadn’t heard of before. Some sort of magnetic tape that acts as indicator to US pilots that a target is friendly:

And each Alizai truck has a magnetic sticker provided by “the Americans.” The Alizais say they were told that the stickers signal to US jets that a vehicle belongs to “friendly” Afghans and not fleeing Taliban or Al Qaeda members.
…
“Don’t worry about the planes,” says Salim Alizai, a Pakistani lawyer and senior Alizai member. “They are searching for the [Al Qaeda] camps and the caves, and they are watching the borders. If you have the magnetic tape, you are fine. Even some of our troops put the tape on their shoulders, and at night, the planes can see them from up in the skies.”