Main Features:
- Wolfson WM8740 DAC Chip + TI PCM2706
- USB signal input, provides I2S interface for decoding
- Works as a DAC+AMP Combo or a standalone AMP
- 2-Setting Gain Switch for impedance matching
- 470mAh rechargeable Li-polymer battery with integrated charging system
- Measures 51*21*82mm, and weighs only 108g
- Battery life is 38hours
- Comes with leather pouch, AC adapter, USB cable, warranty card, and owner's manual

Regarding to the charge function, there is a charge switch on the rear panel. When it is turned to the On position, the charge system is enabled, allowing the Boa to be charged via the furnished USB cable or AC adapter. The Boa can be charged while it is being used, and it will not introduce noise or distortions to your music.