San Diego, Cal/May 21, 1915/Exposition Sta. Numeral "1". Two strikes of duplex cancel (Bomar SD15-01) tying 1904 1¢ Louisiana Purchase + 1915 1¢ Pan-Pacific in combination with 10¢ Special Delivery on cover to Ohio with attractive Expo. label, cover opened for display, Extremely Fine and attractive, a very scarce item with the Special Delivery usage. Estimate  $200 - 300. $0 (Image)