First Day of Issue = November 18, 1938
Size: 28.00 mm x 21.50 mm
Quantity printed = 4,700,000
Perforated 10.00 x 11.50

Part of an 7 stamp set honoring the 20th anniversary of the republic. Stamp shows a waterfront scene in Riga.

Catalog numbers
Scott 204
Michel LV 268

For more information check out the links below
Riga