Heavy Duty Quality Bumper or Siderail Bracket for CB, Scanner, Two Way Radio Antenna Mount Bracket with 3/8 x 24 threads - ProComm JBC482 Heavy Duty Quality Bumper or Siderail Bracket Use with CB, Scanner, Two Way Radios Antenna Mount Bracket accepts antennas that have 3/8 x 24 threads and attach cable to UHF SO239 connector