[Bkrum]

I have six 51 Topps two players panels and am trying to learn more about them. Were they ever sold to the public in this way? I’ve seen 51 topps packs which were single cards. I’ve also seen them sold in the form of a game but it appeared those were separated into individual cards as well. Where do the perforated two players panels come from? I also have one from the Ringside set and one from a non-Sports set. Any idea how rare these are? Does anyone have any for sale?