Eliminating Buzzing Noise caused by ground in some car speakers / home stereo .No external power supply, this noise isolator can achieve a clear speech/music by eliminating the current noise in some car speakers / home stereo .Works with any portable device that has 3.5mm audio jacks, for your Car /Home Stereo.Compact and lightweight, it will not take much space and can be easily taken .Item type: Audio Interface: 3.5mmFrequency response: 20HZ-20KHZAudio input: stereoColour:As ShownMaterial:plasticPackage Contents:1 x Audio frequency common ground isolatorOnly the above package content, other are not included.Note: Light reflection and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.