Bolt

A bolt is a form of grooved fastener with an external helical male thread that engages the interior female thread of a nut. Bolts are closely related to and often confused with screws.

A screw is different from a bolt because it does not take a nut, and its helical thread is used to penetrate (cut into) a softer material (such as wood).

This distinction is not always clear, and screws are someimes regarded as bolts without a nut.

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Category:Hardware (mechanical)