The self-tapping screws produced by FIXDEX can be drilled directly without drilling holes and no nuts are required. The thread is divided into male thread and female thread. Generally, the thread on the bolt is a male thread, and the thread on the nut is a female thread.

Self-tapping screw: Refers to a nut that does not require a female thread, and it drills a female thread into the material while screwing in.
Ordinary screw: The thread on the ordinary screw is a male thread, and the thread on the nut is a female thread.
"Self-attack": refers to the ability to "attack" in.
There are many types of self-tapping screws, and the more common structural designs are plastic and sheet metal self-tapping screws.
The self-tapping screw made of plastic cannot be put on the nut because the pitch difference is too far.
There are about four kinds of self-tapping screws for sheet metal, basically all of which can be used for nuts. Self-tapping screws are triangular teeth. It is not easy to distinguish between self-tapping screws and extrusion screws made of sheet metal. Basically, the difference is not visible to the naked eye. Self-tapping screws made of plastic can be seen at a glance because of the large pitch gap.
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