1597 and 1597a Americana Issue, 15c Flag.  MNH Large Block Tagging and Small Block Tagging Variety. 

Expand your Americana collection with this tagging variety! 1597 was issued in June 1978 with both Large Block Tagging (Scott 1597) and with Small Block Tagging (1597a). This stamp replaced the non denominated "A" rate contingency stamp and paid the new first class postage rate of 15c. First class postage had recently increased from 13c to 15c effective May 29, 1978. The Large block tagging comes only from plate 38650, the other five plates in the series all being small block tagging (in this case freshly broken from plate 38797).  See second picture to view tagging under UV light. 

Several sets available. You will receive a fresh MNH set of two singles similar to the photo. 

I always ship on the next business day after payment has been received and always use real stamps on my mailings. 15 Year APS member and longtime collector. Please feel free to ask any questions. Moneyback if not satisfied less the cost of postage. I will gladly combine postage should you purchase more than one item. In that case, just wait for an invoice before making payment.

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