Av-jefe Tcm-128st Lapel (Tie-clip) Camcorder Stereo Microphone 3.5mm Connector & On/off Switch Element: Electret Condenser Operating Voltage: 1.5V DC (Battery Included) Frequency Response: 30 - 18,000 Hz Impendence: 1000 Ohm +/- 30% (@ 1KHz) Cord Length: 40 ft