unused Block of Four $1.00 Parcel Post (Q12), T. margin block of four with partial imprint and plate no. 6264, extraordinarily well-centered within wide margins, beautiful rich color, lightly hinged (T. stamps have minor natural gum skips), both B. stamps never hinged, couple minor selvage thins, the stamps are very fine-extremely fine and exceptionally choice, with 1999 P.F. certificate which states that the B. pair is never hinged, almost a remarkable rarity (Scott retail for a full imprint and plate no. block of six is $20,000.00), Scott retail $1,700.00 (as simple block of four) photo