The Avantree Relay Premium Airplane Bluetooth Adapter is a sleek black accessory that allows users to connect their headphones to all airplanes equipped with a 3.5mm jack. This adapter, with model number BTTC-218, is designed by Avantree and requires 1 Lithium Ion battery (included) for use. With Bluetooth connectivity, this product ensures a seamless audio experience for users, making it a convenient and high-quality addition to their home audio setup. Its compact size and included batteries make it a practical choice for on-the-go use as well.