WOW! You could use these "magic" bullets to vibrate concrete! I know, because I am a mason. The wiring shorted during 2nd use. Placing bullets in ring has to be done delicately or the "ring" will tear. I think as long as male is on top and caution is used, you may get a lot of use from this item. Great idea and near perfect design..Better wiring connection is necessary. Fix it please!