External USB Sound Card USB to Jack 3.5mm Headphones Audio Adapter Mic Sound Card for PC Computer 2.LED indicators: Microphone-Mute Status, Activity 3.USB2.0 Full-Speed ( 12Mbps ) Specification 4.USB Class Specification 1.1 5.USB Audio Device Class Specification 1.0. USB bus-powered, no external power required. 6.The USB 2.0 External 7.1-Channel Audio Sound Card Adapter. It can work with either desktop or laptop. 7.And with the Xear 3D Sound Simulation software, it extends stereo speaker or earphone to 7.1 channel environment, giving high quality sound enjoyment. 8.Connectors: USB Type A, Stereo output jack, mono microphone input jack 10.Functions keys: Microphone-Mute, Speaker-Mute, Volume-Up and Volume-Down 11.Size: 57 x 25 x 12mm 12.Weight: 25g 13.System:Windows 2000 / XP / Server 2003 / Vista, Linux