GE Speedtronic Mark VI IS200TPROH1B is a Protective Termination Board and is part of the gas turbine and steam turbine control system. Two huge black terminal blocks are located on the left edge of the IS200TPROH1B. Both of these terminal blocks have twenty-four cube-shaped silver metal terminals, for a total of forty-eight terminals. A pair of vertically coupled transformers are located at the top of the IS200TPROH1B. The majority of these transformers are red, with yellow bits on top. A circular red component known as a MOV or metal oxide varistor sits next to each of these transformers.