Diamond Dust Punchboard cards. Basically, they were issued inside gambling devices as tickets. The trick is that there is only one punchboard that actually has the cards in it. The myriad other DDPBs do not have cards. The cards were accordion folded into the slots and punched out with a metal rod. Of the 37 total cards slabbed by PSA and SGC, only three have gotten numerical grades because it was routine to trim off the borders.
The Averill is the nicest known card:
Joe D is typical of the trimmed cards:
The images are drawn from the Salutations Exhibit cards.