As a kid, I loved the Kelloggs 3D cards. They were a nice change from the regular Topps cards each year. Little did I know then that Topps had 3D cards also. Topps produced a test set in 1968. There are a couple different backs. Most that I've seen are blank, but there are also some with info about the cards being not for resale or distribution.
Here is one card I own and one I wished I owned.
1968 Topps 3D Boog Powell (Blank backed)
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Topps 3D Prototype of Brooks Robinson. I also enjoy being married so I passed on it when it came up for auction. Would lover to see it in person someday.
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