[Connector: SO239 to 3/8 x 24] Standard 3/8" x 24 threads, Fits cb whip antennas with 3/8-24 mounting threads( for TRAM, Fire Stick firefly cb antenna; for Pro Trucker, Francis, Hustler, RoadPro, Browning, Wilson cb antenna,etc.) Fits any mount or mounting surface with a 1/2" (13mm) hole, suitable for most vehicles such as jeep trucks, etc. [High quality durable Material] Ensure durability and low loss, Ensure the stable performance of antenna; Strong and tight connection, keep the antenna mounted firmly on your vehicel [Simple to install] The order of Installation is the so239 stud base, vehicle mount, White insulating washer, metal flat washer, split locking washer, antenna connection nut. (The stud you received have been assembled in the correct order for your reference) Please check the product details page description if you need more details Package include: 1pcs CB Antenna Stud Mount