Motorola PMLN8191 1-Wire Covert Earpiece, Tube, 2.5mm - TLK, SL. Compatible with TLK 100, TLK 110, SL300, SL3500e, SL7000e series with 2.5mm single pin connector. SL Series: SL1K, SL2K, SL1M, SL300, SL500, SL500e, SL1600, SL2600, SL3500e.
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