This disclosure relates to a rugged, polarized connector or adaptor with interlocking end tabs and notches for polarizing a jack to a specific plug, and in one specific embodiment, a QMA-type RF connector where a rugged spanner nut and a rugged jack casing are used to reinforce the mating connector ends. The connector also includes tabs and mating notches on the spanner nut and the jack casing to polarize the connectors without creating a weakness in the rugged connection. A series of tab orientations is illustrated, a method for grounding the spanner nut to the connector, and a method of using the rugged and polarized interface on any type of connector or as part of a connector adaptor or add-on.