cover 1929 (25 May) red band envelope to Peking bearing first issue 5c. and 10c. pair cancelled by square Uliassutai d.s. with Ulan Bator, Chinese Waikwai and Peking c.d.s. with large "T" in triangle alongside, the front with two more strikes of the tax mark with Junk 4c. used as a Postage Due and tied by Peking c.d.s., fine and attractive