"Really Nice Compressor," with controls for threshold, ratio, attack, release, and gain. Bypass and "super nice" switches. The RMS digital detector circuit in this unit causes chattering and gulging noise in the audio, especially at low threshold settings. We modified the circuit to improve the audio quality and give the threshold control better range. Unit is now more accurate, releases fast and consistently, and compressed voice of instruments is cleaner and more detailed with subtle dynamics. Like new condition, with power supply and manual.