LOCKING MINIATURE JACK PLUGS: 2-pole
A small version of the standard 3.5mm jack plug, with a threaded locking-ring to enable a secure mating with sockets that use an external threaded ring. This is a 2-pole connector which, when used with radio mic transmitters, will access the microphone circuit only (the ring is used for line-level inputs on Sennheiser and Trantec systems).
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