Haiti 1931 UPU 50th Anniversary Sunken Die Proof Complete Set Plus Vignettes. Scott 322-323 var

Set of four ABNC die proofs, commemorating Haiti's 50th anniversary of joining the UPU. The two values in the issued colors on India paper, sunk on to cream stock card, mounted on to stout card with acetate protector. Accompanied by two intermediate sunken die proofs with the vignettes of President Salomon and President Stenio Vincent as used in the final stamp, on unmounted card.