First Day of Issue = June 15, 1933
Size: 36.00 mm x 30.00 mm
Quantity printed = 10,420
Perforated 10.00 x 11.50

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

Watermark



Catalog numbers
Scott CB19
Michel LV 226A

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