There are three various types of opening kinds across worker racks, rails and retires: strung, square and unthreaded. Confine nuts permit clients to mount any kind of rail or rack into square opening racks.
Having the option to have a normalized square opening for worker racks improves similarity and makes things simpler to fix. Before square openings existed, a strung opening being harmed may have implied that you required another worker. Presently, you should simply supplant a pen nut.
