Used, Good condition, manual can be downloaded or emailed to you if you like.
From the manual:
The Unity 300 has 4 mono channels with discrete low noise microphone preamps and 4 stereo line level channels. The mic channels have input gain controls, insert jacks, two band EQ, two post fader auzillary sends, pan controls, and rotary level controls. Phantom 48v power (globally switched) is available to all the XLR mic input connectors. Two stereo returns with level controls to the L/R mains can be used as effects returns.