Allen bolt

Al·​len bolt | \ ˈa-lən- How to pronounce Allen bolt (audio) \

Definition of Allen bolt

: a bolt with a hexagonal socket in its head that is designed to be used with an Allen wrench The Allen bolt is integral to the crank and remains in it when the crank is removed from the spindle.— Eugene A. Sloane, Sloane’s New Bicycle Maintenance Manual, 1981

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First Known Use of Allen bolt

1972, in the meaning defined above

History and Etymology for Allen bolt

Allen Manufacturing Co., Hartford, Connecticut

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The first known use of Allen bolt was in 1972

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Cite this Entry

“Allen bolt.” Dictionary, Merriam-Webster, Accessed 26 Sep. 2020.

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