The MFJ-345T has a ⅜ - 24 connector. connector. See the MFJ-345S for a SO-239 connector. MFJ’s RuffRider mounts feature extrawide four inch lip and large reinforcing tabs on each side safely distributes load over your vehicle’s lip. Two large set screws on each end locks your mount in place. A scratch proof rubber guard protects your vehicle’s finish. Secures large VHF/UHF and medium size HFantennas. Adjustable angles. Perfect for MFJ’s large RuffRider VHF/UHF Antenna series or MFJ’s Hamtenna HF whips. Has 17 feet low loss coaxial line and terminated with a PL-259 connector. Allen wrenches and weather protection caps are included.