SMSL SD 793II DAC Decoder DIR9001 PCM1793 OPA2134 Coaxial Optical Input Headphone AMP All aluminum alloy shell, knob and button. Signal input can choose, with LED indicator. Built-in headphone amplifiers, can perfect driver mainstream low impedance fever headphones. Universal power adapter (100-240acV). Color: Black/Black with Silver available, please check in our store.