Good working unit. Includes IEC power cable and rack mount bolts and washers.

The Behringer Multicom Pro MDX4400 is a 1U rack-mount, 4-channel analog dynamics processor designed for live sound and studio applications. It combines IKA (Interactive Knee Adaptation) compression, peak limiting, and expansion/gating to manage audio signals. The unit offers independent control over four channels, or two stereo pairs, with comprehensive LED metering for input/output levels and gain reduction. 

Key features and functionalities include:

• 4-Channel Compressor/Limiter: Provides four independent, high-grade VCA compressors with IGC (Interactive Gain Control) peak limiters.
• IKA Technology: Features IKA (Interactive Knee Adaptation) for combining hard-knee and soft-knee compression characteristics.
• Control Parameters: Includes adjustable threshold, ratio, attack, release, and output gain, along with an auto-function for attack/release times.
• Sidechain/Filters: Includes a switchable high-pass filter in the control signal path to prevent low-frequency signals from dominating the compression.
• Connectivity: Features servo-balanced inputs/outputs on XLR and 1/4" TRS connectors, with switchable operating levels (+4 dBu / -10 dBV). 

It is widely used for controlling vocal dynamics, instruments, and managing stereo sub-mixes in PA systems, broadcasting, or recording setups.