1939 Sc 580I New York World’s Fair Scott 715

1939. New York World’s Fair.
Catalog numbers: Scott 715, Standard Collection 580I, Michel 694A, Yvert 710.
Issued on: May, 1939.
Perforation: line 12½.
Printing: Collotype.
Size: 33 x 22 mm.
Color: Blue, brown.
Face value: 50 Russian kopek.
Quantity: 510,000.