2Pack 2Pin Clip-on Covert Acoustic Tube earpiece compatible with 2-pin Motorola radio devices. Two-pin standard diameter ear 2.5mm and 3.5mm stereo; space of two-pin 8mm. Ear bud style headset with built-in line microphone; covert acoustic tube provides clearer sound. Parent tube SPK has excellent concealment which makes communication more private. Metal clip and PTT and the microphone provided real hands free; easy to press and keep your communication private. Compatibility: For the following Motorola portable two way radios: 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, VL50. 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. Notice: If the sound quality for receiving starts to get fuzzy, please disconnect the clear tube earpiece and blow it out with an air can, because the air in the tube may affect performance. If you clean the tube earpiece and the issue still persists, please contact the seller.