Characteristics:

1. Rear audible system only
2. No display, warning distance by audible sound
3. Suitable for 2 or 4 sensors.

Technical data:  

1. Working voltage:DC10~25V  
2. Max power: <5W
3. Working temperature:-40 -+80   
4. Alarming distance: Sound 1.5m (5ft)
5. Alarm Voice: 50dB