Pro Trucker 3/8" x 24 Chrome Stud for CB & Amateur Radio Antennas Standard thread 3/8" x 24 and fits the standard SO-239 Coax connection Designed for larger antennas with the durable and premium construction Compatible with many different springs, mounts, antennas, etc. and fits on most makes and models Fits a 1/2" hole for mounting purposes on different surfaces such as a bumper or roof top Overloaded Mobile is an authorized re-seller of Pro Trucker products