These are a type of threaded inserts which can be used for multiple threads. Unlike full profile threaded inserts, these are not customised to fit just a single thread. These can be used for different pitches or profiles; hence you don’t have to worry about the exact measurements of the threads https://www.tappexinserts.com/. This makes them easy to use for multiple threads and will also be easily available. You can also buy these inserts in bulk and store for future use.