metric self drilling screws

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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Black phosphate drywall screws are specialized fasteners designed specifically for the installation of drywall and related materials. They are characterized by a unique black phosphate coating that not only enhances their aesthetic appeal but also provides increased corrosion resistance. This coating is produced through a chemical process that creates a layer of iron phosphate on the screw's surface. This is crucial in construction environments where exposure to moisture and varying temperatures can lead to rust and degradation of standard screws.


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