A connector comprising: a shell having a chamber, the shell having a mating end configured to be mated with a mating connector, the shell holding at least one contact; and a coupling mechanism rotatable about the shell, the coupling mechanism comprising an inner coupling nut and an outer coupling nut separate from the inner coupling nut, the inner coupling nut having threads configured to be threadably coupled to a mating connector, the inner coupling nut having a track defined by track walls formed into an outer surface of the inner coupling nut, the outer coupling nut having a cavity receiving the inner coupling nut, the outer coupling nut having a post extending into the cavity and being received in the track, the post engaging the track walls, wherein the track includes a circumferential groove having an upper track wall and a lower track wall, the track having a tightening slot extending transversely downward from the lower track wall, the post configured to be received in the tightening slot when the outer coupling nut is rotated in a tightening direction such that the outer coupling nut is locked to the inner coupling nut during tightening, characterized by: the track having an untightening slot extending transversely upward from the upper track wall, the post being received in the untightening slot when the outer coupling nut is rotated in an untightening direction such that the outer coupling nut is locked to the inner coupling nut during untightening of the coupling mechanism; and by: the post being released from the tightening slot back to the circumferential groove such that the outer coupling nut is unlocked from the inner coupling nut when the coupling mechanism is fully tightened and the connector is fully mated to the mating connector. a shell having a chamber, the shell having a mating end configured to be mated with a mating connector, the shell holding at least one contact; and a coupling mechanism rotatable about the shell, the coupling mechanism comprising an inner coupling nut and an outer coupling nut separate from the inner coupling nut, the inner coupling nut having threads configured to be threadably coupled to a mating connector, the inner coupling nut having a track defined by track walls formed into an outer surface of the inner coupling nut, the outer coupling nut having a cavity receiving the inner coupling nut, the outer coupling nut having a post extending into the cavity and being received in the track, the post engaging the track walls, wherein the track includes a circumferential groove having an upper track wall and a lower track wall, the track having a tightening slot extending transversely downward from the lower track wall, the post configured to be received in the tightening slot when the outer coupling nut is rotated in a tightening direction such that the outer coupling nut is locked to the inner coupling nut during tightening, characterized by: the track having an untightening slot extending transversely upward from the upper track wall, the post being received in the untightening slot when the outer coupling nut is rotated in an untightening direction such that the outer coupling nut is locked to the inner coupling nut during untightening of the coupling mechanism; and by: the post being released from the tightening slot back to the circumferential groove such that the outer coupling nut is unlocked from the inner coupling nut when the coupling mechanism is fully tightened and the connector is fully mated to the mating connector.