Rare version of the Octave OC-2
The Boss Octaver OC-2 reproduces three separate tones:
the original tone, a second tone one octave below the original, and a third tone 2 octaves below the original.
Great for adding low end and apparent thickness to your sound. Each part has a separate volume control.
This particular Boss Octaver OC-2 has a handful of small paint chips and scratches.
The sticker on the bottom is missing but according to the Bossarea calculator, it was manufactured March 1983 in Japan. Serial number 280500.