10c Pale Ultramarine, Special Delivery (E10).
Wide top imprint and plate no. 5520 block of six, h.r., lovely pastel color, sometime ago the bottom right corner (about 2-3mm) was broken off due to careless handling and has since been re-attached, otherwise Fine-Very Fine, rare plate block, the five sound stamps have a Scott Retail value of $1,600.00
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