4/40 threaded rod
Why do you need threads at both ends?
When I want clevises at both end I'll solder one on one end and have the adjustment at the other theaded end, Having threads at both ends is just makes one more thing that could come loose
If it's about looks? and you want to use all thread but don't like the look of all those threads, slide the right size brass or plastic tube over to hide the threads.