Line length: about 1.2 /3.9ft Plug: 2 pins for Microphone: noise of mic: 36 dB (maximum) Mic reference operating voltage: 3V DC Mic current consumption: 0.5mA (maximum) Voltage range of middlehead: 1~10V DC Mic impedance: 2.2 ohms (maximum) Mic sensitivity: 60 dB + 2 dB Horn: Horn Impedance: 150 +15% Ohm Horn sensitivity: 130dB Horn frequency range: 20-20KHz Horn Effective Test Range Frequency: 30-5000Hz Horn distortion: less than 5% Horn rated power: 10 mW Horn maximum power: 15mW Horn Abnormal Sound: 0.5V (50Hz-5KHz) No Abnormal Sound Applicable models (including not limited to) For KPG KPG27D,KPG29D,KPG48D,KPG49,KPG55D,KPG56D,KPG62D,KPG66D, KPG69D,KPG70D,KPG74D,KPG75D,KPG77D,KPG82D,KPG87D For -D7,-D7A,-D7AG,-D7E,-F6,-F6A,-F7,-F7E,-G71,-G71A,-G71E,-K2,-K2A,-K2E,-K2ET,-21,-21AT,-21BT,-22,-22A,-22At,-22E,-25,-26,-27,-28,TH31AT,TH41AT,TH41BT,-42,-42A,-42AT,-42E,-45,-46,-47,-48,-55,-75,-77,-G71,-205,-215,-225,-235,-235A,-235E,-315,-415 Colour:white :ABS Package Contents: 2 x 2Pin Dual Earphone Earpiece Mic Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.