concrete insulation nails

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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While not fasteners in the traditional sense, washers are often used in conjunction with bolts, nuts, and screws to improve their performance. Washers distribute the load of the fastener over a larger surface area, helping to prevent damage to the material being fastened and reducing the risk of loosening due to vibration. There are several types of washers, including flat washers, lock washers, and fender washers, each serving specific functions in various applications.


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