Captive fasteners are an engineered class of fastener designed for a permanent hold (captivation) within a target assembly or housing, including upon servicing. They provide a secure joining, and avoid fastener loss or damage that might be caused by a loose part.
A captive fastener is often made with thread locking, press-fitting, or broaching to accomplish an anchor-hold within a larger assembly housing. However, a captive fastener may also be melded with the material into which it is joined, either through cold forming or welding.
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