First Day of Issue = July 1, 1941
Size: 17.50 mm x 25.00 mm
Quantity printed = 3,130,000
Perforated 10.00 x 11.50

Russian stamps overprinted with "LATVIJA 1941. 1. VII" and issued under German occupation.

Catalog numbers
Scott 1N18
Michel DE-LV 5

For more information check out the links below
German Occuptaion