Thread extension with thread AND socket in different sizes

[Teea]

I will merge these two. The rod is wider than the current nut/sleeve and therefore I am considering if there are thread extenders that can be used before I replace either of them. If they exist, what are they called?

 

[Larsgöte]

I am going to join these two. The rod is wider than the current nut/socket, and therefore I am considering if there are thread extenders that can be used before I replace either of them. If they exist, what are they called?

Splice nut, extension nut

 

[Kvisthberg]

I will merge these two. The rod is wider than the current nut/socket and therefore I'm considering if there are thread extenders that can be used before I replace either of them. If there are, what are they called?

Switch to a longer screw.