PA21 may refer to:
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Pennsylvania Route 21
Pennsylvania Route 21 (PA 21) is a long east–west state highway in the US state of Pennsylvania. The western terminus of the route is at the West Virginia state line in Richhill Township, where PA 21 continues into West Virginia as West ...
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Pennsylvania's 21st congressional district
Pennsylvania's twenty-first congressional district was a congressional district in northwestern Pennsylvania
Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Nor ...
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Piper PA-21, an aircraft prototype
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Pitcairn PA-21, an autogyro of the 1930s
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