Xtenzi Microphone External Bluetooth Mic Assembly for Farenheit TI-769NB 652NB 740NB 931NB 718NB Car DVD Nvigtion Replacement mic Microphone for Fahrenheit car sterio kit, Adopting electret condenser cartridge with high sensitivity , low impedance , anti noise and ant jamming capability , it's highly improved the speech quality of hand free car kit communication system. Easy to install with double sided tape and mount, 3Meter Long cable, Standard Operation Voltage: 4.5V Operation Voltage: 1.0V-10V.DC