cover 1866 entire (no side flaps) to Chittagong, bearing 1865 1a. brown and 2a. orange tied by Singapore "172" duplex and blue f.a.c. with, on reverse, faint "SINGAPORE/SHIP LETTER/PAID" d.s. in red partly overstruck by "CAL:G.P.O./BG 1 ANNA" h.s. in blue, Calcutta Ship Letter d.s. and arrival c.d.s. The only recorded cover from Hong Kong with the duplex. Photo
cover 1866 entire (no side flaps) to Chittagong, bearing 1865 1a. brown and 2a. orange tied by Singapore "172" duplex and blue f.a.c. with, on reverse, faint "SINGAPORE/SHIP LETTER/PAID" d.s. in red partly overstruck by "CAL:G.P.O./BG 1 ANNA" h.s. in blue, Calcutta Ship Letter d.s. and arrival c.d.s. The only recorded cover from Hong Kong with the duplex. Photo

Details
cover 1866 entire (no side flaps) to Chittagong, bearing 1865 1a. brown and 2a. orange tied by Singapore "172" duplex and blue f.a.c. with, on reverse, faint "SINGAPORE/SHIP LETTER/PAID" d.s. in red partly overstruck by "CAL:G.P.O./BG 1 ANNA" h.s. in blue, Calcutta Ship Letter d.s. and arrival c.d.s. The only recorded cover from Hong Kong with the duplex. Photo