Need to ask about a lot?

UNITED NATIONS - NEW YORK OFFICES 1982 Conservation and Protection of Nature IMPERF PLATE PROOFS complete set as lower left corner BLOCKS of 4 with UN emblems in the margins, Scott 290Pl & 291Pl, superb never hinged mint, 20c with inked fingerprints on the reverse as security device. Very fresh & scarce, only 50 pairs of each value produced. (2 blocks = 8 proofs)