DockerDave

They were designed so if they were drilled, once the drill bit shorted the two covers it caused a tamper alarm. I got called out to a bank one horrible winters night to a tamper fault on the bell box which you could hardly see because of the snow. I asked the assistant manager if he hand a sweeping brush. He thought i was going to clear the snow on the path for my ladders. Should have seen his face when i twatted the delta bell with the brush loosening all the snow that had blown in the vent causing high resistance.