MX SMA Male Plug Terminator 50 Ohm Connector (MX-2919)

SMA ports show up constantly on RF test gear, wireless modules, and transmitter/receiver equipment, and any port left open while the rest of the system is live is a potential source of signal reflections that can distort readings or interfere with the active ports nearby. This terminator screws straight onto an unused SMA port and holds it at the standard 50-ohm impedance most RF equipment is built around, the same principle as terminating an unused BNC port but matched to SMA's much smaller connector size. It's a cheap, essential accessory for anyone running multi-port RF equipment where not every port is active at the same time.