Optimum mechanical and electrical characteristics of the current-carrying parts are assured through the use of high-conductivity, high-strength aluminum alloys. Transfer contacts utilize high-pressure, silver-to-copper construction.  There are only three moving current transfer contacts and of these only one is an exposed separable contact subject to environmental conditions.

Throughout the current path all bolts, nuts, and pins are stainless steel, minimizing the possibility of corrosion.  A galvanized structural steel channel base supports the insulators and live parts. The mechanical parts and rotor bearings are designed for durability to withstand cantilever stresses, ensuring long-lasting service in all types of environments.  All parts have been designed to be uniform across the product line.  As a result, parts are easier to stock and are more readily available from the factory. The TTR8 has also been seismically tested.