HQRP® Hands Free Headset with D Shape Earpiece and Push-to-talk Microphone;. Microphone Sensitivity: -34 ± 2dB RL=2.2KOhm Vs=3.0V(DC) 1KHz 0dB=1V/Pa;. Microphone Resistance: 2.2KOhm 1kHz (RL=2.2KOhm).
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