Alpha Delta UHF Connector Coaxial Cable Surge Protectors have SO-239 connectors and are rated for 200 or 2,000 watts at frequencies up to 500 MHz.
They are not DC-blocked, so they will pass control voltages in applications requiring the coaxial cable to carry both RF and DC voltage. They may be easily mounted for the most effective grounding with a 1/4-20 bolt or stud (depending on model) in a single hole or as a bulkhead-mount through the grounding panel.
$45

More info: https://www.dxengineering.com/parts/alf-att3g50uhp#overview