metal expansion anchor

Countersunk self-drilling screws are a specific type of screw designed to allow for a flush finish in various materials, including wood, metal, and plastic. The term countersunk refers to the conical shape of the screw head, which allows it to sit seamlessly against the surface of the material being fastened. This design is particularly advantageous for aesthetics and functionality, as it eliminates any protruding heads that could be prone to snagging or catching on other objects.


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A wafer head screw, as the name suggests, has a flat, thin, and circular head, resembling a wafer. The head is usually larger than the screw's body, providing a broad bearing surface that distributes the load evenly and reduces the chances of damage to the material being fastened. The self-tapping attribute refers to the screw's ability to cut its way through the material it is inserted into, forming threads as it goes, hence the term self-tapping.

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