eranton USB Bluetooth Audio Music Receiver Adapter 3.5mm Stereo Output for Car Home Stereo Working Mode: 3.5mm male to male auxiliary output, streaming music to your speaker wirelessly. Please note the usb is used for power suppy only. To make it work, you need to connect the receiver with your speaker via 3.5mm aux cable Updated bluetooth tech features high quality audio transmission ,Transmit up to 33 feet away with line of sight; Better build quality than the generic ones, much tougher and last longer Turn your wired stereo system to wireless ,perfect for home stereo and car stereo systems Powered via USB port , no battery is needed