Hastings Aluminum Bus clamp 6.5" clamp body is the ultimate substation grounding tool for maintenance crews. Thanks to its maximum fault current rating of 54KA at 15-cycles and 39KA at 30-cycles, this hanger stud clamp is quickly and easily able to provide ground connections, saving time and cost. The aluminum body and 9-1/2" copper bar have a size range of 6.625" maximum and 0.398" minimum. It also weighs just 8.7 lbs.