1948 December 1:
Windsor (2) post office opened. (source: Maine Philatelic Society. 1995. The Post Offices of Maine: A Rarity Guide)
1964 April 6:
The circular postmark is 31–32 mm in diameter.The outer vertical height of the four bars to the right of the circle is approximately 19 mm.
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2020:
Windsor post office, 519 Ridge Road; Windsor, Maine. 04363. Lat./Long.: N 44°18′10″ x W 69°34′21″
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today:
Windsor (2) post office is still in operation.