B-Stock, Swissonic HAD-1; 24-Bit 96KHz high-performance Headphone-Amp and DA Audio Converter with USB 2.0 connection; Headphoneoutput with ¼ jack; Stereo analog RCA line Inputs; digital S/PDIF Input; Stereo analog RCA line outputs; digital S/PDIF Output; Surround Multichannel playback via S/PDIF Output (AC3/DTS Decoder); for headphones 32 - 600 ohms; Powersupply: 15 V Powersupply, Requirements: Class Compliant, Includes USB cable, Power Supply, B-Stock with full warranty, may have slight traces of use