This ear-hook microphone offers a very smooth frequency response with reliable and predictable performance. Double over ear headset mic is an replacement for the original wireless microphone system. This microphone is made of rugged and ultra light-weight steel, designed to meet the challenges of day-to-day use in the gyms, theaters, classrooms and houses of worship. A foldable headband allows it for easy storage and carrying. Manufactured with extreme care and the highest quality components, the professional hands free microphone headset delivers exceptionally clear, articulate sound with reliable performance in an extremely low profile design. · Product Parameters: Type Condenser Directivity Omnidirectional Mic Capsule Diameter Φ4.0mm Sensitivity 22mV/Pa（-32dB±2dB） Frequency Range 80Hz - 20KHz Output Impedance ≤2.2KΩ Standard Operation Voltage 2.0V-10V.DC Cable Length 1.2M(47.24 inch)