Post Office Seal, 1919, black, multiple perfs. Block of four with a variety of perfs, perf 12 at left and right, perf 9½ at top and bottom, perf 9 horizontally in center perf 8½ vertically in center, o.g., right stamps faulty from separation, Fine appearance, the only recorded block of this type. Scott No. OX21 var.  Estimate $200 - 300. $0 (Image)