In 1889, the U.S. Post Office opened bids for the contract to print postage stamps. Bid sheets were sent to printing companies, including the American Bank Note Company, which held the contract for the previous issue. This new bid specified a request for stamps in either of two sizes - the same size as the current issue, or a smaller size. This potential smaller sized issue would be printed in colors different from the previously issued stamps. To demonstrate the colors, stamps of the previous issues were printed in the new colors, overprinted with "SAMPLE A.", and included in the blank bid sheets. These are listed as the Type L specimens.

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