This adaptor is made from high quality chrome plated brass and has one internal 1” – 14 TPI thread and one external ISO 228/1-G1 thread. The adaptor can be used for installations where the cable has to be accessed from the side and to convert an external 1" 14TPI thread to an external ISO 228/1-G1 thread. The external thread fits the N239F revolving nut which is supplied with many of the AC Antennas products.