Alloyed shell, weather proof function for outdoor use; 1/3' CMOS; 30 infrared LEDs with 15 meters night vision range; Built-in microphone for audio monitoring; Key-press switch receiver, with on/off button; Alloyed shell, weather proof function for outdoor use; 1/3' CMOS; 30 infrared LEDs with 15 meters night vision range; Built-in microphone for audio monitoring; Key-press switch receiver, with on/off button; 4-channels available to avoid interference; Min 100m tansmission distance without block; Including adjustable bracket, easy installation. Simple package information: