GE 1912 Semi-Official Airmail, MI. 4a Margaret Fair

VF used. May 1912, light, dull-blue semi-official air post stamp for Margaret Fair Leipzig to Lindenthal flight. Stamp shows a two winged men and is inscribed, "Margaret Fair Volksfest, Leipzig, 18 May 1912; 50pf and Flugpost Marke. Lithograph. Violet and blue postmarks available. Send note if you have a preference.