Remote Speaker Mic for Motorola EX500 EX600 GP344 GP388 PRO5150Elite PTX700Plus. PRO5150Elite PRO7150Elite PTX700Plus PTX760Plus. GP328Plus GP329Plus GP338Plus GP339Plus GP344 GP388 GP644 GP688. The remote speaker mic allows you to talk and listen without having to move a radio so makes the use of the walkie-talkie more convenient.
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