Cards without a back!
I don't know a whole lot about how baseball cards are printed. I do know that they are printed on large sheets and then sliced up into individual cards. If the cutting process isn't perfect, you get off center cards or worse.
Since the cards are double sided, the fronts and the backs have to line up pretty well.
Well here's something I've never seen, a card with a completely blank back. Maybe these aren't so rare, but, like I said, I've never seen one. I got this in a repack last year. These repacks are often loaded with 1987 Topps cards (I think approximately a billion sets were produced). I'm actually trying to complete the set in this manner. I could buy the set on eBay but where's the fun in that?
I don't remember how many cards are printed on a sheet. There must be at least a 100 cards, maybe 200. So there must be another 199 or so blank backed cards that were printed along with this one. I'm guessing that most of these got caught by Topps quality control (maybe I'm giving them too much credit but I'd think a blank back card would be pretty easy to spot).
And what were the Pirates thinking with those stove pipe hats? Back in those days I still lived in Philadelphia and the Phillies and the Pirates were in the same division. I got to see those hats a lot.