Description: Eliminates humming and buzzing due to ground loop issues For device with a 3.5mm audio jack such as a cell phone or MP3 player, and an amplifier such as the AUX input in a car or on a home stereo If you hear noise when charging your device but not when operating on battery, then this product should solve the problem Filters out DC current in the signal path Connectors: 3.5mm Male, 3.5mm Female Passive in-line device Size: (approx.)120mm*80mm*25mm/ 4.7*3.15*0.98inch Package Includes: 1 x Audio Curcuit Noice Isolator