Speaker dimensions: 50 mm 32015% impedance Sensitivity: 110 dB Range of frequencies: 20 Hz–20 kHz Mic: 6.0 x 2.7 mm Sensitivity of the microphone: -42÷3dB 2.2K O is the microphone impedance. Directionality: all-encompassing Length of cable: 2.2M, $0.15 LED DC5V5% is the working voltage. Current of operation: ≤100mA USB headset jack