This is a hinge block for Edison models C,H,K and several other reproducers. The thread size is #0-110, same as original reproducers. These are made of solid brass and are nickel plated. These can be used to repair a reproducer that has a broken hinge block but, if the threaded stud is broken off in the reproducer body and you are not experienced in removal techniques, then you should probably send your reproducer to an experienced reproducer repair person. Edison reproducers models N and O require a different thread size which is #1-64. I also make these and have them available.