who can identify this vintage card - "DAD-48" ?

[B.Degnan]

I have a mystery card to identify within a pile of miscellaneous cards 
acquired recently.  On the card is printed "DAD-48 Computer Dynamics, Inc. 
1985."  The cable jack is a 50-pin female.  I am having trouble locating 
specifics on the web, and I have looked everywhere.   Where might one use 
this card?  Is it PCI SCSI?

A picture is worth a thousand words.  Here is a page I put up with some 
pictures
http://vintagecomputer.net/dad-48/

Thanks in advance.

Bill
Wilmington, Delaware
vintagecomptuer.net