Else World audio mic uses a high-quality voice and low noise. This audio mic is with a built-in PRE-AMP process chip. After multiple times frequency selected it can restrain the noise efficiently. Pure timber, strong dynamic, built-in AGC circuit. Lots of strong points: Low noise, high fidelity, wide operating voltage & long transmission distance, etc. This audio mic is the best choice for the CCTV camera audio monitoring and safety system.