bolt shield

Metal expansion nuts, often referred to as expansion anchors or expansion inserts, are specialized fasteners that expand when a bolt or screw is threaded into them. They typically consist of a cylindrical body with slits along its length or an expandable design that facilitates outward expansion. The main purpose of these nuts is to create a secure grip within a substrate, such as concrete, wood, or metal, thereby preventing loosening due to vibrational forces, temperature fluctuations, or stress.


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The 'head' of the bolt refers to its top part that sits above the threaded shaft. It's the part that provides the gripping surface for the tool used in installation or removal. The hexagonal shape offers several advantages over other head designs. Firstly, it allows for better torque application, enabling precise tightening without slipping. Secondly, the six-sided profile can accommodate larger wrenches or sockets, which can generate more torque, ideal for heavy-duty applications.

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