China, Airmail, 1921, 90¢ olive green & black, in combination with 1923, ½c + 1c + 1½c Junk issues all tied by Peking cds's on 1923 flight cover to Tientsin, purple Tientsin flight cds and receiving backstamp, Very Fine. Scott No. C5+248-250  Estimate $200 - 300. $0 (Image)