cover 1877 envelope (opened out for display and tear) to USA showing on reverse very fine "CUSTOMS/KIUKIANG" despatch c.d.s. (14.9) and bearing an obverse Japan Koban 5s. brown (faults) cancelled by cork type, showing "I.J. POSTAL AGENCY/SHANGHAI" (18.9), YOKOHAMA/PAID ALL" (29.9) and "SAN FRANCISCO/PAID ALL" (18.10) c.d.s. adjacent, the last two in red. Rare use through the Costoms service prior to the issue of the Large Dragon stamps. Photo