cover 1926 (30 Dec.) "red band" envelope from Ulan Bator to Kalgan with 5m. + 25m. in combination with "Junk" 4c. cancelled in transit at Harbin; 1927 (9 May) large part envelope (opened-out) from Ulangom to Ulan Bator with 20m. cancelled by boxed d.s. (large); 1927 (20 Dec.) native envelope (opened-out) from Tsetserlig - Mandal to Kalgan with 20m. cancelled by boxed d.s. in red-brown in combination with "Junk" 4c. cancelled at Harbin and 1928 (19 Dec.) native envelope (opened-out) from Ulan Bator to Kalgan with 20m. + Third Definitive issue 5m. in combination with "Junk" 4c. cancelled at Manchouli in transit; some faults. An interesting quartet