 
    Specification:
Protable speaker
Directly used with USB card or SD card 
Available for PC/MP3/MP4/Mobile phone Power Output: RMS 3W× 2 Impedance: 4Ω 
Frequency Response: 90Hz-20KHz 
Sensitivity: 400mV SNR ≥ 80dB 
Power supply: 5V by USB cable Built-in high-capacity lithium ion Rechargeable battery