1964 Topps Stand Up #17, Roberto Clemente.
This is one of my favorite Roberto Clemente cards.
The 1964 Topps Stand-Ups were issued as a stand alone set of 77 cards (though some players appear twice, creating 55 unique subjects).

They came in five-cent wax packs with 5 cards per pack.

Because they were a separate test-style set and not part of the main 1964 Topps baseball issue, distribution was more limited than the flagship Topps set.