Product Features: Action Throat Mic Headset Finger PTT for easy using In-Ear Speaker Vibration Sensors Transparent flexible acoustic sound tube Soft plastic earbud fits snugly to ear 1 spare plastic earbud included Compatible Cobra 1-pin Models: MT Series: MT100, MT115, MT200, MT250, MT300, MT525, MT550, MT600, MT615, MT650, MT750, MT800, MT850, MT975 PR Series: PR237, PR240, PR245, PR260, PR350, PR375, PR385, PR550, PR560, PR580, PR590, PR650, PR3000, PR3100, PR3175, PR3180, PR3500, PR3550, PR3575, PR4000, PR4200, PR4250, PR4300, PR4700, PR4750, PR5060 LI Series: Li-3900, Li-4900, Li-5600, Li-6000, Li-6500, Li-6700, Li-7000, Li-7020, Li-7200, Li-7500 CX Series: CX80, CX105, CX105C, CX107, CX110, CX312 CXT series: CXT85, CXT88, CXT90, CXT94, CXT95, CXT125, CXT135, CXT145, CXT175, CXT225, CXT227, CXT235, CXT237, CXT275, CXT280, CXT345, CXT400, CXT420, CXT425, CXT450, CXT545 CXR Series: CXR700, CXR725, CXR750, CXR800, CXR825, CXR850, CXR875, CXR900, CXR920, CXR925, CXR950 CTW Series: CTW135P, CTW285P DC FRS Series: FRS132, FRS237 MRHH Series: MRHH100, MRHH125, MRHH200, MRHH325, MRHH330, MRHH425, MRHH475 More compatible models, please contact us by email for more details.