This receive only headset has a transparent acoustic tube (for use with a remote speaker microphone)
Function Description: This earpiece (Φ3.5mm pin) is used with remote speaker microphone only.
Compatible Radios:TC-268S, TC-368S, TC-270, TC-370, TC-265, TC-265S, TC-365, TC-365S, TC-508, TC-518,TC-600, TC2108, TC2110, TC-700, TC-780M, TC3000, TC3600, TC3600M, TC-610, TC-620, TC1600, TC-980, TC-780, TC-610P, TC-268, TC-368, TC-880GM, TC-580, PD70X,PD70XG,PD78X,PD78XG,PT-580,PT580H,TC-446S,TC-700P
Speaker Specifications:
Sound Pressure Level: 112±3dB @ 1KHz (single part);
Rated Power: 10mW Max. Power: 30mW;
Distortion (typical): <5% @ 1KHz;
Speaker Impedance: 32Ω±15% @ 1KHz
Operating Temperature: -20℃~60℃