I've found a screw like this. It doesn't have a whole thread, it's threaded both near the tip and near the head but not in the middle.
What's the purpose of this?
Furthermore the thread is partially serrated, why?
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Sign up to join this communityI've found a screw like this. It doesn't have a whole thread, it's threaded both near the tip and near the head but not in the middle.
What's the purpose of this?
Furthermore the thread is partially serrated, why?
Doing a quick image search on Google, it looks like Dan D.’s is correct. “That looks like a decking screw.” It is also referred to as a “terrace screw.”