SL Series : SL1K, SL2K, SL1M, SL300, SL500, SL500e, SL1600, SL2600, SL3500e. SL7000 Series : SL7550, SL7550e, SL7580, SL7580e, SL7590, SL7590e. Swivel Earpiece with PTT Microphone for Radio. 180°Rotation allows you to wear the earpiece on either your left or right ear.
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