Attaching the clamp to the grounding cable requires the use of a ferrule. Ferrules are compressed on the strands of the cable
to provide a low resistance permanent connection. The size of the ferrule is determined by the size of the cable. Ferrules
are available in aluminum or plated copper. Plated copper ferrules can be used with either aluminum or bronze clamps.
Aluminum ferrules can be used with aluminum clamps only. Two ferrules are required for each assembly therefore they
are sold in pairs. Ferrules are manufactured to the specifications of ASTM F 855. *STB stocks tin-plated copper, unshrouded