The device, which will be mounted high on the wall in a dormitory housing some 65 prisoners, does no damage but it's ray penetrates the skin about 1/64th of an inch over an area about the size of a CD, causing a sensation that's been equated to opening an extremely hot oven. The pain stops when the target gets out of the way of the beam. It is controlled remotely via a joystick and a camera mounted on the ray itself. Deputies at Pitchess think it should help break up fights between inmates and keep deputies from having to hurl themselves into harm's way when inmates get unruly.