ZDD Ground Loop Noise Isolator eliminates noise interference that may occur when the audio source is connected to the playback device with no signal loss. Plug this audio noise filter in and it instantly removes buzz, hum, and static from your car audio system, radio, home stereo, or speakers. Restores clear sound quality. Plug and play design ensures simple operation. Connect the ground loop isolator directly to the vehicle or speaker's AUX port, then plug the aux cable into the audio source. Experience immediate improvement and effective noise reduction. This noise filter requires no power and has no built-in battery. Wide compatibility with any device featuring a 3.5mm jack, including cell phones, laptops, tablets, computers, MP3 players, and speakers. Can be used with a Bluetooth adapter in car audio or home stereo systems. Lightweight and portable design made from durable polymer materials for high strength, wear resistance, and light weight (2.4 x 0.75 x 0.75 inches, 0.05 lb). Compact size, with a diameter smaller than a quarter, making it easy to carry.