1 2 expansion anchor

When selecting a self-drilling screw for roofing, factors such as the thickness and type of roofing material must be considered to choose the appropriate screw length and diameter. Proper alignment during installation is also key to achieving optimal performance. Contractors and DIY enthusiasts alike appreciate the ease of use, which comes with a caveat the correct tool, typically an electric drill or impact driver, is necessary to drive these screws effectively.

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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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