unused Freaks & Errors, 20th, ten unused items comprised of single, pair and eight blocks of four, incl. three drastically misperfed pieces, three overinked blocks and three double impression blocks (nos. 525d, 528c two) and single (no. 530a) of the perforated 1918 Offset issue (the Offsets have a Scott retail of $320.00), mostly fine-very fine lot