I'm guessing those are non-lethal crowd control devices. They transmit microwaves that cause temporary extreme pain, without lasting damage. Forgot the name of them, but someone else will know. They were featured on a tv episode of Future Weapons (Discorvery Channel?). The huge military guy who is the host of the show volunteered to be hit with the waves and in just a couple seconds he collapsed to the ground, IIRC.