The effect is centuries old. It has been performed throughout the world for just as long. A spectator asks a question and the bell rings back, answering the spectators questions. This bell hangs on a beautiful crystal clear acrylic arm. There is absolutely no question that the bell is not attached to any strings, threads, etc. There is absolutely no way the bell can be controlled other than by the spirits. This effect can be performed under test conditions. You can even isolate the bell and stand under a clear box. Bell can be handed out before and after demonstration there is absolutely nothing to find!