9 Electric and Electronic Controlling Units and Feedback Controllers; Servomotors and Electronic Controllable Drives; Electric and Electronic Circuitries, Switches, and Parts Thereof for Servometers and Electronic Controlling Drives; Electronic Amplifiers, Operational Amplifiers and Comparators for Feedback Controllers; Hand or Foot Actuated Regulators; Transformers; Circuit Boards; Holders for Plug in Circuit Boards; Electric or Electronic Instruments for Displaying, Registering and/or Indicating Volume, Length, Speed, Weight, Temperature, Frequencies, Voltages, Resistance and Capacities; Electric and Electronic Tacho Generators Constituting a Part of a Tachometer and Further Used for Controlling the Speed of a Drive