Mail accepted by the U.S. Post Office Department at dockside to be carried by ship was subject to a surcharge equal to the normal postage. This service was available until the U.S. entry in WW II in December 1941. Currently, the number of solo uses of the 6¢ sheet stamp paying double the domestic first-class rate  (i.e., 3¢ first-class pluss 3¢ late fee) to cover the Late Fee is: 1.

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Description: Letter to Honolulu, Hawaii posted at dockside in San Pedro, California on March 5, 1941 and stamped "LATE FEE".

Owner/Source: Dickson Preston article in Summer 2008 edition of The Prexie Era.

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