1c-3c 1918-20 Offset Issues (525-526, 528, 528B, 529-530, 536). Plate blocks of six, No. 528 with monogram, second 528 with offset in selvage, Nos. 525, 528B, 529 and 530 Mint N.H., few others h.r., few with small faults, bright colors, Fine-Very Fine