WMD MSCL stereo compressor. Includes module, power cable, original box.

From WMD:

Stereo analog compressor in 4hp

MSCL is a stereo compressor in 4 hp designed for your master bus to help "glue" your mix together. Inspired by the DBX "Over Easy" style compressor, it features independent attack and release knobs, output gain, and an all-in-one knob function for compression which decreases threshold, increases gain and ratio all with one turn.  Limit Switch allows MSCL to act more like a peak limiter. The threshold switch lets you compress signals of different amplitudes. It also features a side chain input for classic ducking sounds on stereo tracks. 

CONTROLS

Comp knob: adjusts makeup gain, threshold, ratio simultaneously.

      -  1.25:1 to infinite:1 ratio

Attack Knob: Controls how fast the compressor will react to incoming transients

        Attack speed: 0.15ms/dB to 0.1s/dB

Release Knob: Controls the speed in which the compressor will release.

        Release speed: 0.6ms/dB to 4s/dB

Gain Knob: Adds up to +-35dB on the output

Threshold Switch:  Changes the threshold rainge

       Three ranges (Left to Right) +5dBu, -4dBu, -15dBu

Limit Switch:  Limits the comp knob's makeup gain. Makes the MSCL operate more as a peak limiter.

       Three selections (Left to Right): Inf, 9dB, 3dB