This is a unique double denomination note where the back of a One Dollar denomination was printed over the back of a Five Dollar denomination. The back was printed with a heavy ink smear. This note grades gem crisp uncirculated.
Clearly visible on the back of this note from the One Dollar impression are the Pyramid, the denomination ONE and the Great Seal of the United States.
Although there are double denominations known, this is the only one reported where the second denomination is printed over the first denomination.
Below is an authentication letter from Frederick Bart for this unique discovery double denomination error. Frederick Bart is the author of United States Paper Money Errors: a comprehensive catalog and price guide.