add An Spdif Digital Audio Output And Standard 3.5mm Audio/microphone Connections To Your System Through Usb. The Icusbaudio2d External Usb Sound Card Lets You Add An S/pdif Digital Audio Output And Standard 3.5mm Analog Audio/microphone Connections To Your System Through Usb - A Convenient Way To Bypass Or Replace An Internal Sound Card Without Having To Open The Computer Case.for Home-theater Quality Sound, The Usb Dac (digital-to-analog Converter) Offers 96khz / 24-bit Sampling Rates For Both Playback And Recording, And A 3.5mm S/pdif Port With Support For Dolby Digital 5.1 Surround Sound (ac3) And Dts Pass-through (note: 5.1 Surround Sound Is Supported In Windows Only).this Versatile Usb Audio Adapter Features An Integrated 3.5mm 4-position Trrs Connection For Your Headphones Or Combination Headset/microphone. Also A Convenient External Volume Control For Quick Adjustments, A Hardware Eq Switch For Bass Or Treble Boosting, And An Led Status Bar To Display The Current Sampling Rate.backed By A Startech.com 2-year Warranty And Free Lifetime Technical Support.