complete mint pane of 100 with stage IV overprint (9.D), includes numerous varieties including "Canal" in antique type at position 26 (9a), "Zone" in antique type at position 48 (9b), "E" of "Zone" faintly printed at position 68 (9.3), and more, never hinged but a few natural gum disturbances, very fine and rare as a complete sheet