Mark-8 Minicomputer Clone Power Conversion Board
The power conversion board is used to convert this power supply to voltages that are compatible with the Mark-8 minicomputer (+5 volts and -9 volts) since it's hard to find a switching power supply with those voltages out of the box.
Be sure to watch the YouTube series on the Mark-8 Minicomputer clone build to get familiarized with the board.