 The world's largest lever frame (191 levers) is thought to have been in the Spencer Street No.1 signal box in Melbourne, Australia, which was decommissioned in 2008.The largest operational lever frame, meanwhile, is located at Severn Bridge Junction in Shrewsbury, England, and it contains 180 levers, although most of them have been taken out of use.The lever frame is located in the signal box, which can be a building at ground level or a tower, separated from or connected to an existing station building.