1. Input terminals: DCФ3.5DC Plug 4               

2. Working voltage: 3.7V                  

3. Maximum output power. 90MW                    

4. Noise level :25db                           

5. Signal to noise ratio (SNR):>=90db                

6. Power supply: 600mA lithium battery             

7. Rated operating time:>=28H               

8. Noise Reduction Type: One-way feedback                                     

9. Speaker diameter: Ф40mm                     

10. Speaker Impedance: 32Ω                    

11. Speaker frequency response: 20Hz - 20KHz                                 

12. Speaker sensitivity: 115dB                      

13. Wire length: pvc wire, 1.2m