This is by far the strangest card that I received in last month's care package from Max. As you can see, I determined that it is a 1989 Star brand card featuring a player for the Hagerstown Suns, the Orioles' AA affiliate at the time. But that's the extent of my knowledge. There is no name, no position, and no stats on the back. See for yourself:
Thanks to the Trading Card Database, I was able to find scans of the entire 1989 Star team set for the Suns, but none of the cards pictured match the blank one that I possess.