Awesome 500 series compressor for bass (and everything really). Made by Peter Montessi, the maker of the REDDI and many other world class preamps and pro audio gear. It's one of the those things that just makes instruments sound better by running through the circuitry, but the controls are very wide-ranging and versatile. Amazing for vocals and bass. Sounds especially rich and punchy with the distortion button engaged.

This is in used good condition, has only been used at my studio. Ships in the original box, though not sure if it's the original box for this exact unit as I have multiple of these.