Brand New, never used, in perfect condition but open box item (without manual but includes power supply).

Behringer product info:

Ultra-compact monitor headphone amplifier for studio and stage applications
Personal ''more me'' mixer – mix a mic plus a monitor signal and hear them via headphones
Flexible Mic In and Mic Through connectors plus Ground Lift switch
Stereo Monitor input with dedicated Monitor Level control and Mono/Stereo switch
High-power headphone output on 1/4'' and 1/8'' jack connectors
DC 12 Vadapter included

The ultra-compact MICROMON MA400 is the ideal personal monitor mixer for the performer who is always asking for “more me.” Featuring a flexible Mic In and Mic Thru connectors and Ground Lift switch, as well as stereo Monitor input with a dedicated Monitor Level control and Mono/Stereo switch, the MA400 has everything you need to satisfy even the most-demanding performer on stage.

Connections
The MA400 features XLR Thru jacks and provides superb noise-free operation. Just connect to the Mic Input and send a line from the Mic Thru to your main mixer. You can even use studio-grade condenser mics, as the MA400 will pass +48 V phantom power, if your mixer is so equipped. The Phones jacks accept both ¼ " and 1⁄8" headphone and earbud connections, making the MA400 ideal for hardwired IEM (in-ear-monitor) applications, such as singing drummers and keyboardists. The MA400 comes with a dedicated 12 V DC power supply and an LED to indicate when it is powered up.

Capable of either stereo or mono operation, the MA400 is a powerful little mixer that allows you to control two independent sources, such as a microphone and the monitor feed from your main mixer. Simply adjust the MA400‘s Monitor Level control