Product Description Code 3 Supply Ear Hook Earpiece with Microphone and Push-to-Talk Button Designed for Rugged Professional Applications. Product Specifications Soft Flexible Ear Hanger for long term wear Built In Microphone with Clothing Clip Shock & Water Resistant Reinforced Cable Can be Worn on Either Ear Product Compatibility Occasionally, you have to push hard (and wiggle) the connector to get it in to fully seat into the radio. This is to keep a water resistant seal between the connector and the radio case to keep water from getting into the connector on the radio. If the connector isn't fully seated, you are only able to hear and not transmit. Motorola 2 prong M1/ GP300 - 2 Prong Plug with 2.5mm and 3.5mm plugs with 8mm spacing: XTN Series: XTN446, XTN500, XTN600 XTN XV Series: XV1100, XV2100, XV2600, XV4100 XTN XU Series: XU1100, XU2100, XU2600, XU4100 XTN AX Series: AXV5100, AXU4100 CLS Series: CLS1110, CLS1413, CLS1450, CLS1450C, CLS1450CB Motorola Spirit Series: SV10, SV11, SV11D, SV21, SV12, SV22, SV22C, SU210, SU22, SU22C, SU220 VHF / UHF Spirit, Spirit Pro, Spirit Pro+, Spirit HP 10 Spirit MU Series: MU11, MU11C, MU11CV, MU12, MU12C, MU12CV, MU21C, MU21CV, MU22CVS, MU24CV, MU24CVS, MU24CVST Spirit MV Series: MV11, MV11C, MV11CV, MV12, MV12CV, MV21C, MV21CV, MV22CV, MV24CVS CP Series: CP88, CP040. CP100, CP110, CP125, CP150, CP200, CP250, CP300 GP Series: GP2000 , GP2100, GP300, GP308, GP68, GP88, GP88S SP Series: SP10, SP21, SP50+, SP50 CT Series: CT150, CT250, CT450, CT450LS PRO Series: PRO1150, PRO2150, PRO3150 P Series: P040, P080, P1225, P1225LS DTR Series: DTR410, DTR550, DTR610, DTR650 Other Series: GTI, GTX, LTS2000, VL130, PMR446, ECP100, Mag One BPR400, EP450, AU1200, AV1200 RDX Series: RDV2020, RDU2020, RDU2080D, RDU4100, RDU4160D, RDV2080D, RDV5100, RDU5100 RM Series: RMU2040, RMU2043 RMU2080, RMU2080D, RMM2050, RMV2080 FDC: FD-150A, FD-450A, FD-160A, FD-460A Blackbox Series: Blackbox-V, Blackbox-U (M1 Connector)