onelinkmore SO239 to SO239 Coupler 4-Hole Flange, UHF Female to Female Gender Changer, PL259 Coax Cable Extension Adapter, Chassis Mount Feed Through for Ham CB Radio Antenna, Go-Box Pack of 2

A go-box (or go-kit) is a portable, self-contained amateur radio station built into a case or enclosure that can be quickly deployed for emergency communications, field day operations, or portable activations. Clean antenna connections on the exterior of the box — using panel-mount couplers like this one — allow antenna cables to be connected and disconnected without opening the enclosure or disturbing the internal wiring. The 4-hole flange provides a permanent, secure mount that maintains alignment even after hundreds of connect-disconnect cycles in the field.

Standard UHF female 4-hole flange connectors require a center hole of approximately 16mm (5/8 inch) for the connector body, with four mounting holes on a square pattern at approximately 25.4mm (1 inch) center-to-center spacing. The flange is secured with M3 or #4-40 screws through the panel. Panel thickness up to approximately 6mm works with standard thread engagement; thicker panels may require longer screws or counterbored holes.

Yes. While the 4-hole flange is designed for panel mounting, the coupler functions as a standard UHF female-to-female barrel adapter when used freestanding. PL-259 plugs thread into both sides, joining two UHF coaxial cables end-to-end. The flange simply provides the option to secure it permanently to a surface. This dual-use makes the flanged version more versatile than a standard barrel coupler for installations that may eventually be made permanent.

A standard hex-nut panel mount connector uses a single nut tightened against the panel face to hold the connector in place. Repeated PL-259 threading and unthreading can gradually loosen the hex nut, causing the connector to rotate and eventually work loose from the panel. A 4-hole flange uses four screws distributed around the connector body — each screw shares the rotational load, and the larger contact area with the panel distributes mechanical stress. Flanged connectors are standard in commercial and professional radio equipment for this reason.

The coupler body is suitable for outdoor use, but the SO-239 ports are not weatherproof in the IEC IP-rated sense — they do not prevent water ingress when no cable is connected. For permanent outdoor installations, apply self-amalgamating tape around connected PL-259 joints to seal against moisture. When ports are unconnected in outdoor locations, protective caps should be used. For inherently weatherproof antenna feedthrough, purpose-built weatherproof coaxial entry glands are the appropriate choice.

Many radio enclosures and go-boxes have multiple antenna connections — one for HF and one for VHF/UHF, or multiple antenna ports for different bands. The 2-pack allows both antenna entry points to be equipped simultaneously. For single-antenna enclosures, the second coupler serves as a spare or can be used in a second build.