Registered letter mailed August 13, 1940 from Birmingham, England to the U.S. Patent Office, Washington, D.C., franked with King George VI 3d violet and 2½d blue definitives totaling 5½d postage.
Bearing censor tape “Examiner 5288 / P.C. 90” and registration label Birmingham No. 8719, with multiple red wax seals and Washington arrival backstamp dated September 9, 1940.

This cover represents early WWII British censorship, from the height of the Battle of Britain period, showing careful postal handling of registered diplomatic and technical mail to the United States.
A prime example of WWII postal censorship, transatlantic registered mail, and British wartime postal procedures—of strong appeal to collectors of WWII history, censorship markings, and KGVI postal stationery.

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