Specifications: Collect audio evidence as important as capturing video evidence. Pick up every sound with this super high gain micro audio system. This high gain mini microphone is the best for CCTV professionals. Type: Audio Hidden Microphone Monitor Range: 50㎡- 80㎡ Working Voltage: DC 3V - DC 18V Current: 5mA Output Electrical Level: 0 - 6V Frequency: 100 - 10kHz Frequency Response: 2.5dB Output Impedance: 600Ω Wiring Method: Red Line Connected to the Power + Pole White Line Connected to the Recording Device Audio Input or Amplifier Audio Input Size(L x D): 43cm x 1cm/16.93 x 0.39 (Approx.) Notes: Due to the light and screen setting difference the item s color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Audio Hidden Microphone Please contact us to better resolve any issues before leaving neutral or negative feedback. If you have any questions please contact customer service.