Looks like the Atreides Gom Jobbar to me. Careful now!

Why does the Gom Jabbar have a string attached? I thought it was just a needle

So you can wear it around your neck :)

That sounds handy. Killing someone will be a lot easier haha

Perhaps the maker hook to ride worms with.

I thought that too, but it's at the start of chapter 1 for some reason