The A-175 contains two identical inverters which will take a voltage and output it in an inverted form - so that an input of +5V will be output as -5V and an input of -2V will be output as +2V and so on.
Typical uses are for inverting a modulation CV such as an LFO or Envelope, but can also be used for audio signals, as inverting (a non symmetrical) waveshape is not the same as a 180 degree phase shift.
Two LED’s give a visual indication of the output signal (positive or negative)