TOPPING MK2 Digital Hi-Fi Power Stereo Subwoofer Amplifier 16bit/48kHz USB DAC Headphone Amp All in one machine with Desktop Hi fi, PC- solution. It's not only a DAC, but also an amplifier& headphone amp Support ON/OFF via USB Fully support Android Mobile Device 4.1 or above with OTG connection (Only for Native Android system with OTG function) All in one machine with Desktop , PC- solution