3c rose tied by "DUE 6" marking with Dec 24, 1864 Port Royal, SC cds on cover to Connecticut. "U.S.S. Acacia off Charleston, SC" manuscript.

Union forces reoccupied the city of Port Royal, South Carolina on November 7, 1861. This letter came into Port Royal aboard the Blockader U.S.S. Acacia which patrolled the coast from South Carolina to Florida. The letter was brought into Port Royal with only partial prepayment, and was therefore rated at twice the unpaid portion of the postage [DUE 6]. Had the letter been endorsed by a ship's officer, it would have been treated as a Sailor's Letter and not have required any prepayment.

At Port Royal, the 3¢ postage stamp was cancelled. The letter was placed in a closed bag and carried north aboard a ship.

According to Richard Graham, only 10 Covers Recorded with "DUE 6"