Purple High Quality Stereo Handsfree Headset Mic Earphone Plugs - Free Microseven Logo Gift Frequency Range: 20Hz~20kHz Sound Pressure Level: 107dB3dB/100mW Total Harmonic Distortion: &lt;=5,(Input Power: 10mW; Frequency Range: 20Hz~20kHz) Crystal clear and high quality voice for both talking party, noise cancellation High velocity element for excellent stereo effect