GP series: GP328PLUS, GP338PLUS, GP339PLUS, GP344, GP344R, GP366R, GP388, GP388R, GP644, GP688. EX series: EX500, EX560, EX560XLS, EX600, EX600XLS. 1 x Acoustic Tube Earpiece Headset. - Hidden microphone at the end of the PTT, convenient to transmit.
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