Features: 1, Easy Plug and Play Installation. USB bus powered--Requires no external power. 2, Stereo Headphone output lets you jam with your computer and can also be used for monitoring with active monitor speakers. 3, Variable-speed file playback function for MP3, WAV, AIFF audio files perfect for easy learning and practicing. 4, USB Guitar Link Cable is a professional tool that enables you to turn your PC computer into fantastic working platform on which you can use the classic effects, in the studio as well as on stage. 5, Support OS: Microsoft Windows XP (SP2) and Windows Vista,for Mac OS 8.5 or above. Specification: Size: 25X51X25MM Input port impedance: high resistance (hi) 250k ohm, low resistance (low) 400k ohm Headphone port output impedance: 50 ohms Large output level: -2dbu, 2*3.7mW @ 100 ohms Package include: 1 x Guitar Cable Notes: Please allow slight dimension difference due to different manual measurement. Due to the difference between different monitors, the picture may not reflect the actual color of the item. We guarantee the style is the same as shown in the pictures.