This is a non-OEM replacement power supply for Zebra/Eltron label printers, LP series and others. It's also used by some laptops and other devices that require a 20VDC 3.25A regulated power supply and need a 5.5mm x 2.1mm x 10mm plug.
It's new in the original bag. It uses a "mickey mouse"-style grounded line cord (IEC 60320 C5); a new one is included.
The plug is a normal 12V barrel connector with a 5.5mm OD, 2.1mm ID, and a 10mm length.