hex washer head lag screw

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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In addition to their sealing capabilities, neoprene washers also provide vibration and shock absorption. When used in conjunction with self-tapping screws, they help to mitigate the impact of vibrations that can loosen fasteners over time. This is particularly crucial in automotive and machinery applications where constant movement and vibration are present. The resilient nature of neoprene ensures that the screws remain securely fastened, reducing the risk of mechanical failure.


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