Usage Tips: Eliminates buzzing noise caused by ground loops in some car speakers or home stereo systems. This noise isolator helps achieve clear o by reducing electrical interference without requiring an external power supply. Compatible with any portable device featuring a 3.5mm jack for use with car o or home stereo systems. Compact and lightweight design ensures easy portability and minimal space usage. Item type: Ground Loop Noise Isolator Interface: 3.5mm Frequency response: 20Hz–20kHz Input: Stereo Size: 59 x 20 x 18mm Material: Plastic Color: Black Package Contents: 2 x Ground Loop Noise Isolators or 4 x Ground Loop Noise Isolators Note: The package includes only the items listed above; other products are not included. Light reflection and differences in display screens may cause slight variations between the color of the item in the image and the actual product. Measurement may vary by +/- 1-3cm due to manual measurement.