Nikon D850 Menu Manual page 262

Wireless
transmitters
(0 251)
262 Technical Notes
• USB Cable Gaskets and Connector Covers: Use a UF-4 connector
cover for USB cables and UF3-RU14 USB cable gasket to
help prevent accidental disconnections. Before
connecting the cable, attach the UF-4 at the camera end
and the UF3-RU14 at the end that connects to the
wireless transmitter.
UF-4 (attaches to connector for camera)
UF3-RU14 (attaches to connector for WT-7)