4-Pin Noise-Cancelling CB Microphone Noise-Cancelling Circuitry: Removes unwanted background noise from outgoing transmissions Rugged Construction: Heavy-duty hardware and ABS housing to withstand the rigors of the road Metal mesh grille 9-Foot Cable: Extra long and flexible for driver convenience Fits all Cobra CB Radios with 4-pin screw-on connectors (Also most other professional style CB and amateur radios with 4-pin screw-on connectors Integrated strain relief on cable at the microphone connector 4-Pin Connector Pin 1 Shield: Ground Pin 2 White: Audio Out Pin 3 Red: Transmit Pin 4 Black: Receive Specifications: Type: Dynamic Impedance: 5000 ohm Freq. Response: 150-4000Hz Cable: 9Ft Coiled Connector: 4-pin female locking ring Housing: ABS Plastic Additional Model #'s 221-M77 M77 HGM77 UPC: 028377310843
