Air Post stamps. 1934, Animals and Airplanes, 5k-2t, complete set of nine used on registered cover from Kyzyl to Netherlands, no backstamp, VF (Image)

Air Post stamps. 1934, Argali - Mountain Sheep, 25k deep purple, triangle stamp in tete-beche pair, imperforated between stamps, negligible soiling at the bottom, unused, no gum, F/VF, A. Farberov certificate (Image)

Air Post stamps. 1936, Airplane and Dirigible, 5k-3a, complete set of ten with two 25k stamps (perforation 14 and 11), nicely centered and post office fresh, full OG, NH, VF and scarce never hinged (Image)

Air Post stamps. 1936, Seaplane above Dragon, 1a bluish green, diamond stamp with blank label and margin at bottom right, watermark ''1'' on selvage, CTO with full OG, VF and scarce item (Image)