The first Topps baseball cards appeared as a subset from the issue of 252 "Magic Photo" cards
The V. K. Zworykin card is a very rare 1948 Topps Gum Magic Photo card #5H, one of eight inventor cards in a subset of the main issue.
It is very nicely developed and in very good condition. These cards originally came with a blank front. One would then moisten the front by spitting on the wrapper and holding the card against it. Then exposing the card to light to develop the photo. These are about the size of a postage stamp, which would explain their rarity.
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