Features: These headset microphones give you loud, clear, high-fidelity sound. Sensitivity: -52dB+3dB/-52dB-3dB. Impedance: less than or equal to 2.2 kΩ. Material: nylon rope, iron wire, rubber. Microphone: 6.0 x 5.0 mm. Frequency range: 100-16kHz. Signal-to-noise ratio: >60dB. Plug diameter: 3.5mm. Operating Voltage: 2.0V Earphone cable: about 96cm. Directionality: single point. Color: Black. Package includes: 2 headsets. Notice: 1. This is a directional microphone, please make sure that the microphone above the hole (visible after removing the sponge) is aimed at your microphone when using it. 2. Before wearing the headset, please do not turn on the power and volume of the voice amplifier to avoid howling.