A standard-polarity SMA male connector has a 0.9mm diameter center pin surrounded by barrel with inside threads, and the standard SMA female connector has a center sleeve surrounded by a barrel with outside threads.

There are also reverse-polarity ("RP") SMA connectors in which the pin and sleeve are swapped so that the "male" RP-SMA has a center sleeve surrounded by an inside-threaded barrel, and the "female" RP-SMA has a center pin and an outside-threaded barrel.

[6] The SMA connector uses a polytetrafluoroethylene (PTFE) dielectric that contacts along the mating plane.

For that reason and that they are just rated for a limited number of connection cycles, an SMA connector is not usually a good choice for metrological applications.

A 5⁄16 inch torque wrench is required for this, set to 3–5 in·lbf (0.3 to 0.6 N·m) for brass, and 7–10 in·lbf (0.8 to 1.1 N·m) for stainless steel connectors.

It is also advisable to inspect and clean out loose debris from the internal surfaces with compressed air or a gas duster can before mating.

These are similar to the SMA connector, but with the geometries incompatibly scaled, and a metric thread to prevent accidental intermating.

Wi-Fi equipment manufacturers have widely used RP-SMA connectors to comply with specific national regulations, such as those from the FCC,[18] which are designed to prevent consumers from connecting antennas that provide additional gain[citation needed] and therefore breach Part 15 compliance.