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What is an Allen Key?


What is an Allen Key?

An Allen key is a must-have tool for mountain bikers.

©Beth Puliti
Definition: An Allen key, also called a hex key or an Allen wrench, is a hexagonal L-shaped bar that drives in screws and bolts with hexagonal sockets. Allen keys can be used to assemble bicycles, adjust seat height (on certain bikes) stem and handlebars, remove pedals, and more. The most commonly-used Allen keys can be found in multi-tools.

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