$3.50 U.S. Capitol Dome: Unlike previous Priority and Express Mail issues, which featured pictures related to the U.S. space program, stamps of 2001 use photographic images of Washington, D.C., landmarks. The self-adhesive Priority Mail stamp shows the Capitol Dome gleaming against a dark sky. Looking at the stamp through a special U.S.P.S. decoder will reveal scrambled identifying marks saying, "Priority Mail."
2002 Priority Mail
$3.85 Jefferson Memorial: This Priority Mail stamp features the Jefferson Memorial. Thomas Jefferson’s signature can be seen at the lower left when viewed through a special decoder lens. This is the third stamp in the National Monuments Series.
2002 Express Mail
$13.65 US Capital Dome: This stamp's also got a hidden image on it. The US flag on the top right corner of the stamp can be seen through a decoder lens.
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