1. Head shape
Self-tapping screws have a variety of head shapes.
2. Screwing method
The basic way there are two kinds of external and internal screwing.
3.Types of threads
There are many types of threads for self-tapping screws, including self-tapping threads， machine threads , drywall nail threads, fiberboard nail threads, and some other special threads.
4. End form
The end form of self-tapping screws mainly has two kinds of tapered end and flat end.
Self-tapping screws have a variety of head shapes.
2. Screwing method
The basic way there are two kinds of external and internal screwing.
3.Types of threads
There are many types of threads for self-tapping screws, including self-tapping threads， machine threads , drywall nail threads, fiberboard nail threads, and some other special threads.
4. End form
The end form of self-tapping screws mainly has two kinds of tapered end and flat end.
Self-tapping screw structure
