5 16 tapping screw

Butterfly screws, also known as toggle bolts, are a type of fastener that features a pair of wings that fold during installation and expand once they are inside a pre-drilled hole. The design allows for a stronger grip on hollow walls, such as drywall, where regular screws might not provide sufficient anchoring. Butterfly screws are particularly useful for mounting heavier items like televisions, where the risk of falling can be a significant concern.


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The primary structure of a wedge-type anchor consists of a threaded rod, a nut, a washer, and the wedge itself. The threaded rod, often made from durable materials like steel or stainless steel, is inserted into a pre-drilled hole. As the nut is tightened, the wedge is forced against the inner wall of the hole, causing the anchor to expand. This expansion generates a powerful frictional force that locks the anchor in place, providing exceptional holding power.

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