Connector Type: CB antenna stud mount adapter with SO-239 connector Function: Antenna Stud Mount, installs between the mount and antenna; Standard 3/8" x 24" Threads Fit for all standard Antennas Mounts and Accessories Basic but Strong: The Replacement Stud Mount is made of all-copper nickel-plated material to ensure a strong and tight connection, not easy to break; White washer provides good insulation and keeps the antenna from grounding out on your mounting point Wide Compatibility: The CB Antenna Mount fit Mobile/ in-Vehicle CB Radio Antenna Mount standard 3/8" x 24 threads to fit Fire-stick antennas, which perfect fit for off-road vehicles, vans, trucks, RV, motorhomes, boats, and so on Easy Installation: The Antenna Mount Adapter is suitable for mounting bracket holes are about 9-14 mm ( 0.35-0.55 inch ) and comes with 3/8-24 threads for easy installation and mounting; The stud you received have been assembled in the correct order for your reference This CB Antenna Stud Mount Adapter is great for antennas and most antennas. Can be used on any mounting surface with 3/8" x 24" m) holes, suitable for most vehicles such as jeep trucks, etc.