1927, 10k dark blue and yellow brown, a white spot over ''7'' in ''1927'' variety at right (position 26), full OG, LH, F/VF centering, Est. $100-$140 (Image)

1927, 10k and 15k, complete set of two in horizontal pairs used on First Day Air Mail cover from Moscow to Paris, tied by ''1.9.27'' date stamp, Paris ''5.9.27'' arrival marking, mostly VF, Est. $150-$200 (Image)

1922, red surcharge (type III) 1200m on Russian Consular stamp of 10k lilac on green and buff network, position 10 (broken ''F'' in R.S.F.S.R.) of 25-stamp setting, full OG, previously hinged, VF, Soviet Philatelic guarantee, Z. Mikulski opinion (stamp position 5 mentioned by mistake), only five stamps of type III are in a complete sheet, C.v. $975, Est. $600-$750 (Image)

1922, red surcharge (type I) 1200m on Russian Consular stamp of 2.25r dark blue on green and buff network, position 21 (spaced a dot after ''F'' in R.S.F.S.R.) of 25- stamp setting, full OG, previously hinged, VF, Z. Mikulski opinion, C.v. $1,950, Est. $900-$1,200 (Image)

1931, Airship over Kremlin, 20k dark carmine, four-side margins imperforated single with vertical position of watermark Borders and Rosettes, full OG, NH, VF and scarce watermark variety, Est. $150-$200 (Image)

1931, Airship Constructions, 10k-1r, complete set of five, all with perforation L12 1/2, full OG, NH, mainly VF, Est. $200-$250 (Image)

1931, Airship over the Arctic Region, 50k dark gray blue, error of color, nicely centered, full OG with tiny gum wrinkle, which is not really important, NH, VF, C.v. $900, Est. $400-$500 (Image)

1931, Airship over the Arctic Region, 50k dark gray blue, error of color on thinned (no more then 0.075mm) paper, left sheet margin single, full OG, NH, VF (LH on selvage) and very scarce, Est. $500-$700 (Image)

1932, Airship over the Dnieper Dam, 15k gray black, engraved printing, perforation 10 1/2, nicely centered for this difficult stamp, full OG, light trace of hinge, VF, this stamp has been sold at Cherrystone Auction in May 2012, lot #2502, for $1,500 plus appropriate fees, Est. $1,200- $1,500 (Image)

1932, Airship over the Dnieper Dam, 15k gray black, engraved printing, enlarged margin at top with nice margins at other sides, full OG, previously hinged, VF and very scarce stamp of only 100 printed, several expert's hs on reverse, Est. $2,000- $2,500 (Image)

1935, Special delivery registered cover from Kharkov to Mannheim, franked by five commemorative stamps, including Airship over the Dnieper Dam 15k gray, engraved stamp with perforation 14, which is very scarce, all appropriate markings and arrival ds on reverse, VF, Est. $300-$400 (Image)

1937, 1r black, buff and red brown, souvenir sheet of four of appropriate size 165x90mm, practically flawless, full OG, NH, VF, C.v. $450, Est. $150- $200 (Image)

1935, 1k-50k, complete set of ten, fresh colors and nice centering, full OG (25k with minor gum disturbance at top), NH, VF and scarce in never hinged condition, Est. $1,000-$1,300 (Image)

1935, 1k-50k, complete set of ten, post office fresh quality unit, full OG, NH, VF and scarce in such state of preservation, Est. $1,500-$1,800 (Image)

1935, Mikhail Vodopyanov 25k indigo, one of two ''key'' values of the Chelyuskin Rescue set, used in 1938 on illustrated air mail registered cover from Pushkin (Leningrad Obl.) to Kaluga, together with two other commemorative stamps, appropriate markings and arrival ds on reverse, VF, Est. $250-$300 (Image)

1935, 5k, 20k, 80k, three stamps on paper without watermark, Chelyuskin Rescue 1k and 3k, as well as three stamps of Ethnographic set and K. Marx 3k green, the total is nine commemorative values used on cover from Moscow to Germany, marked ''Par Avion'' on reverse, mostly VF and a spectacular item, Est. $150-$200 (Image)

1924, surcharge 10k on 5r green, complete pane of 25, representing different varieties of surcharge and basic stamps, including stamp on position 12 with narrow ''0'' variety of surcharge, full OG, NH, VF, Est. $400-$500 (Image)

1924, surcharge 10k on 5r green, wide ''5'' variety, fresh quality, full OG, barest trace of hinge mark, VF, Soviet Philatelic guarantees, C.v. $1,250, Est. $750-$1,000 (Image)

1932, 50k carmine and 1r green, complete set of two, both with perforation L12 1/2, nicely centered, full OG, NH, VF, C.v. $315, Est. $150-$200 (Image)

1932, 50k carmine rose, perforation 10 1/2, well centered with large margins all around with a part of sheet margin at right, full OG with slight wrinkles as always, LH, VF example of this Air Post and Soviet Union rarity, ex-Maslowski, this stamp has been sold by Cherrystone Auction in April 2017, lot #128 for $11,500, C.v. $30,000, Est. $10,000-$12,000 (Image)

1932 (8.28), Franz Josef Land - Arkhangelsk Prospective Flight postcard and cover addressed to Vienna and Moscow, franked by International Polar Year single stamp of 50k or by a complete set of 50k and 1r respectively, the flight did not take place due to technical difficulties, all correspondences went from Arkhangelsk, all appropriate marking presented, mostly VF, Est. $200- $250 (Image)

1955, North Pole - Moscow Flight, red overprint on 1r multicolored, horizontal pair, left stamp has no dash in front of Moscow variety, full OG, NH, VF, Est. $150-$200 (Image)

1955, North Pole - Moscow Flight, red overprint on 2r black and yellow green, perforation L12 1/2 instead of comb 12x12 1/2, unfolded block of four, bottom left stamp has no dash variety, full OG, NH, VF and rare multiple, Est. $2,750-$3,250 (Image)

1930, 40k ultra and 80k carmine, imperforated complete set of two in horizontal pairs, perfect condition with large margins all around, full OG, NH, VF and rare in pairs, Soviet Philatelic guarantees, N. Mandrovski certificate for each pair, Est. $7,500-$9,000 (Image)

1935, red surcharge 1r on 10k dark brown, horizontal position of watermark Borders and Rosettes, position 14 of 25-stamp setting, tiny natural paper inclusion at left, full OG, barest trace of hinge, VF, Soviet Philatelic guarantee and expert's pencil sign, Est. $900-$1,200 (Image)