21 TURBO-ALTERNATOR SETS, THERMAL AND HYDRO-ELECTRIC ALTERNATORS; ELECTROMAGNETS; SYNCHRONOUS AND ASYNCHRONOUS POWER MOTORS; RAILROAD ELECTRIC EQUIPMENT; MOBILE AND FIXED SUBSTATIONS; POWER SEMICONDUCTORS; CONVERTER EQUIPMENT FOR ALL REGULATED POWER SUPPLIES; GENERATING SETS; ELECTRIC INSULATING MATERIALS; ELECTRICAL INSULATING VARNISHES; HIGH VOLTAGE INDUSTRIAL ELECTRIC SWITCHGEAR; PREFABRICATED PRODUCTS FOR THE ELECTRICAL INDUSTRY-NAMELY, ELECTRICAL PANELS, ELECTRICAL DISTRIBUTION ELEMENTS, AND ELECTRICAL CABINETS; DISCONNECT SWITCHES, SWITCHES, CIRCUIT-BREAKERS, FUSES, LIGHTING ARRESTERS; PREFABRICATED SHIELDING SETS FOR HIGH VOLTAGE AND LOW VOLTAGE; PROTECTION AND SIGNALLING RELAYS; STATIC POWER TRANSFORMERS; STATIC CONDENSERS; ELECTRIC MOTORS AND GENERATORS; CONNECT AND DISCONNECT SWITCHES, RELAYS; HAND OPERATED SWITCHES