A first-day cover of the 1976 Bicentennial stamps, issued at Philadelphia 200 years after the first public reading of the Declaration of Independence.
This comes with a commemorative coin with no face value. I couldn’t get that coin through the scanner (and didn’t try).
For many years, the United States Postal Service and its predecessors printed and sold stamped envelopes for first class mail, for airmail, for non-profit mailing rates, and the like.
I don’t recall collecting these, but I seem to own an envelope full of unused and mint-condition envelopes from the 50s and 60s and into the 1970s.
From the Bicentennial series:
In this series, I only have one specimen of each imprint, in both a #10-size envelope and a #7-size envelope with an embossed indicum. The New York Times notes “The series utilizes a new format for envelopes, using brown laid‐finish stock, with a silhouette in the lower left corner that complements the subject of the indicia.”
Notice that one of these envelopes is for 10¢, and the others for 13¢. First-class postage increased on December 31, 1975 to thirteen cents from ten cents! The ten-cent envelope was issued in October 1975, and the others during the Bicentennial year.