¡ì hi-fi soundtrack voice monitor head¡ì Built-in AGC gain audio circuit¡ì imported ICs, coupling capacitance¡ì metal,vandal proof¡ì 2mm pinhole design¡ì Japan's imports of gold-plated capacitor microphone¡ì Dynamic closed-loop noise reduction circuit
10 to 150 m2Impedance 600 ohmsFrequency 20 ~ 20KhzPower 9 ~ 12VDCSize ¦µ67 * 35mmFor HaiKang, Dahua DVR device