1968 Topps 3-D
1968 Topps 3-D is a 12-card set. Issued two years before Kellogg's inaugural 3D set, 3-D was a "test set" sold in plain white wrappers -- believed to be only in the New York City area. Each card measures 2 1/4" X 3 1/2", a quarter-inch narrower than a standard-sized trading card, have rounded corners, and were produced by a New York-based printing company named Visual Panographics.
The backs were left blank, and the set checklist below is in alphabetical order.
Test cards of Sam McDowell, Brooks Robinson, and of an Italian soccer player were issued before this 12 card set was released. Those cards measures 2 1/4" by 3 1/4" and has the team name on the top but with no player identification. In addition, test cards of Tommy Davis, Rick Monday and John O'Donoghue were issued and recently discovered without either team identification or player identification.