C2 variety, CSS AM112d, "Without CNC Surcharge" on 1949 West Szechwan Air Mail Unit issue, overprinted on Shanghai Dah Tung Airmail stamp $27 blue

C2 variety, CSS AM112d, "Without CNC Surcharge" on 1949 West Szechwan Air Mail Unit issue, overprinted on Shanghai Dah Tung Airmail stamp $27 blue