Features
1. 4 trigger inputs available and triggered by negative pulse/GND(low level signal).
2. Equipped with a high quality audio decoder chip that is able to decode MP3 and WAV audio formats.
3. Built-in a 4MB flash memory by default, which is able to store total of 4 minutes long MP3 files of 128Kbps.
4. Supports max. 32GB micro SD card.
5. Load audio files to the internal flash memory/SD card through the micro USB port based on PC like using a USB flash drive.
6. Supports multiple functions/trigger modes.
7. The function/trigger mode of each input can be set individually through a configuration file.
8. Can be controlled by buttons, switches or relays.
9. Built-in a 10Watts class D amplifier and a 5Watts speaker for a great sound output.
10. Adjustable sound volume through the small blue potentiometer. 
11. Wide power input(9-24V DC) and stable performance.
12. Industrial grade design and strong anti-jamming capability.

Technical Parameters
1. Working voltage: DC 9V-24V
2. Working current: ≤400mA (Input: DC12V)
3. Power Consumption: ≤5W
4. Flash memory size: 4MB(possible to be extended)
5. Audio format: MP3/WAV