SMC connectors provide a good combination of small size and performance and are available in 50 Ω or 75 Ω impedances. It offers excellent electrical performance from DC to 11 GHz. This version is similar to the SMB connector, but it uses a threaded coupling interface rather than the snap-on connection. The threaded coupling mechanism permits a vibration-proof connection which is ideal for semi-permanent connections and for the use in mobile equipments with low VSWR requirements.