THe VDC400 board is NOT part of the DEB package:

The package I received included a "VDC400" board that was NOT part of the DEB package.
One photo is included that shows the VDC board.
It is interesting in that it appears to be an ISA bus version of the VDC controller built into the M24/AT&T 6300/Xerox 6060/Logabax systems.  
I have no idea what the target market would be for such a board, and cannot find any information about it online as of 2018.  I suppose it would be interesting/useful as an "extended CGA" controller card connected to an extra M24 400-line monitor lying around, maybe?


Photos of the outer box slipcover courtesy of N Smith (normanator)