The experts have been stumped here at the Standard Catalog, which typically (but not always) means we’ve been asked to identify an obscure 1970 collectors’ issue.
So I throw it to y’all: What it this card? Recently purchased on eBay by a reader, the card is in a “PSG slab” of some sort (can anyone tell me what THAT is, too?) identifying it as a 1957 Baseball’s Best Ted Williams #56-1 on the front, although the image is unclear. On the back, it clearly is a puzzle piece.
What the [ bleep ] is it?

Rich Klein took a stab at this, noting that the scan makes it impossible to know for sure:
I think that is what is called in the Beckett Data Base 1976 Taylor/Schmierer Bowman 47 #21 Ted Williams.
