Home made tool. I believe I saw this tool in a magazine many years ago. It is used to screw in the threaded rod into the end of a Nyrod Plastic push/pull control rod. The photo shows a plastic wire nut (yellow), a steel clevis, and a short piece of threaded rod in the clevis. The threaded rod is threaded into the clevis so about 5 threads are left empty. The plastic nut is filled with epoxy. Every time I use it I marvel at the simplicity of the tool. A difficult job is made easy.