Wolfson WM8740 DAC Chip + TI PCM2706. USB signal input, provides I2S interface for decoding. 4ch Amp architecture. Line out function, allow it to work as a standalone USB-DAC. 2-Setting Gain Switch for impedance matching (+3/10dB). Powered by 5 AAA batteries. With 5 AAA alkaline, the play time is longer than 100 hours. Measures 55*21*92mm, and weighs 130g. Comes with one silver and one black enclosure, also comes with leather pouch, USB cable, warranty card, and owner’s manual.