1924 Buckingham, Quebec duplex (OC 6 24) ties 1c, 5c Admiral on postcard to Prague, Czechoslovakia, paying scarce 6c UPU postcard rate. The 6c UPU postcard rate was unpopular as the cost had risen and was only 2c cheaper than the ability to send a full letter at the 8c rate. The 6c rate was in effect from October 1, 1921 until October 1, 1925.
