First Day of Issue = June 15, 1933
Size: 36.00 mm x 30.00 mm
Quantity printed = 10,920
Perforated 10.00 x 11.50
Print method: Lithography

Stamp shows an airplane flying through shrapnel fire over the city of Riga. The surtax was for wounded Latvian aviators.

Watermark



Catalog numbers
Scott CB19a
Michel LV 226B

For more information check out the links below
Latvian airmail semipostal stamps
Latvian aviation