steel roof truss bracing

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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Butterfly screws, also known as wing nuts or butterfly nuts, are a distinctive type of fastener that have gained popularity in various engineering and design applications due to their unique shape and functionality. These screws derive their name from their appearance, which resembles a butterfly in flight when the wings are fully opened. The wings serve as handles, allowing for quick and easy tightening or loosening by hand without the need for additional tools.

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