Specifications: Range: 10~150 M2(adjustable) Frequency: 20~20k HZ SNR: 75dB Dynamic Time MIC Import: Large diaphragm for noise reduction, anti-interference, omnidirectional microphone Operating Voltage: 9~12VDC£¬20MA (MAX) Sensitivity: -44DB 1000 HZ Output Impedance: 1000 ohm Processing Circuit: Soundtrack preamplifier circuit, voice-optimized circuit Power Features: Polarity protection circuit, front and rear dual power supply filtering Operating Temperature: -10¡ãC ¡« +70¡ãC Shell Color: ABS Fireproof Material. White or Black Dimensions: 62mm*30mm*24mm Pin hole Type Wiring: Red (positive supply) and black (power ground, signal ground), green (positive signal) Sensitivity Adjustment: Resistance adjustable through the hole in the bottom board. +for larger volume, medium volume set as factory level. Please adjust it properly according to the actual environment and avoid maximum level. Package Contents 1x Audio Monitoring Head