8 self drilling screws

The process begins with drilling a hole in the drywall to accommodate the bolt's anchor. The butterfly bolt consists of two main parts the bolt itself and the spring-loaded wings. When inserted into the pre-drilled hole, the wings collapse, allowing the bolt to pass through the drywall. Once the bolt is pushed through and the nut is tightened from the front side, the wings expand against the inner surface of the drywall, creating a secure anchor point. This design ensures that the bolt not only holds the weight of the mounted object but also withstands any pull-out forces.

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There are several types of expansion anchor bolts available, each with its own unique design and features. Some common types include wedge anchors, sleeve anchors, and drop-in anchors. Wedge anchors are suitable for use in solid concrete and provide a reliable and secure hold. Sleeve anchors are versatile and can be used in various materials, while drop-in anchors are used in overhead applications where the bolt needs to be flush with the surface.

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