Printer's Cliche and Printing Ink.

Overprint Color:
Red and Black

Overprint Size: 12.5 mm x 2.0 mm.
1932 VON GRONAU AIR MAIL ISSUE

Black on C-30

Black on C-31

Black on C-32

Red on C-33

Black on C-34

Red on C-35
1933 F. REIN AIR MAIL ISSUE

Red on C-40

Black on C-41

Red on C-42

Red on C-44