20 Dollars Federal Reserve Bank Note, Brown Seal

The 1929 Federal Reserve Bank Notes were a deliberate downsizing decision — the U.S. Treasury reduced note dimensions that year to cut printing costs, ending the large-format "horse blanket" era that had defined American paper money since the Civil War. Unlike the contemporaneous Federal Reserve Notes with their green Treasury seal, the FRBNs carried a brown seal and bore the obligation of the issuing Federal Reserve Bank directly, not the United States government — a legal distinction that made them a hybrid between national bank notes and true federal currency.

The series was short-lived. Production effectively ended by 1933, and the FRBН designation was quietly abandoned as the New Deal reshaped the banking system.