Electro-Harmonix Superego Synth Engine.
In good condition with minor cosmetic signs of use. However it does come with its original box.
The polyphonic SUPEREGO Synth Engine reinvents sample and hold, performs fluid glissandos and creates oscillator like, synthesizer effects.
It can stack sounds or create infinite sustain, it even lets you tweak attack and decay, or use its effects loop to invent novel synth patches. Indulge your guilty pleasures!