Comet AD-25M - SO-239 to NMO Connector Antenna Mount Adapter
This adapter changes a UHF-Female (SO-239) into a NMO antenna mount. Adapter only... cable assembly not included.
Instructions: First screw the smaller ring onto the SO-239. Then the larger ring with the set screws. Adjust the height of the connector and both collars so the top ring is even with the top of the SO-239. Tighten the set screws against the lower ring. Insert the plunger into the SO-239. You mayor may not need the white spacer depending on your antenna and connector combination. test for continuity and VSWR before transmitting.