This is the eva electronic Sound Stabilizer III. I am selling it because I no longer have the opportunity to use it. Operation has been confirmed. I will also include a custom-made balanced cable (BELDEN 8412 stereo specification). Using it before a Quad Cortex or Kemper significantly broadens the sound range, making it excellent. It can adjust impedance and phase, making it an excellent unit for bassists as well. It was attached to the back of a board, so there are almost no scratches, but please refrain from purchasing if you are sensitive to such things. Thank you.