1c, 2c and 10c 1910-11 Official Postal Savings (O121, O124, O126).
Top or bottom imprint, hollow star and plate no. blocks of 20, first and last with "Butte Mont." double oval cancels, 1c with "Portland Oregon" double ovals, nearly all Fine-Very Fine, the collector thought these are "philatelic" cancels, whatever the case there can not be many (if any others) available
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