This is a super mini audio Bluetooth transmitter and receiver. If you have electronics without Bluetooth this is a perfect product for you. When it works as Bluetooth transmitter, it can wirelessly transmit stereo audio from your non-Bluetooth audio sources such as TV/MP3/CD player and connect to media players/e-readers and more. When it works as Bluetooth receiver, it adds Bluetooth receiving capability to your headphones/home stereo, which enables you to enjoy the convenience of a wireless connection while listening to your favorite tunes. Bluetooth 4.1 receiver compatible with most smartphones and Bluetooth electronics; perfect for home or vehicle audio systems or portable audio devices. Bluetooth enable all 3.5mm media devices (support Bluetooth receiving: speakers/headphones and more; support Bluetooth transmission: MP3/CD/DVD players/e-readers and more). Simply connect to your non-Bluetooth speakers or headphones with the 3.5mm audio cable, streaming music wirelessly from your devices. Streaming music from the music players and audio books for Kindle Fire to your Bluetooth-enabled speaker, easy and convenient. Small, lightweight and durable, you can carry it and enjoy Bluetooth music anytime and anywhere. Easily switch between transmitter and receiver mode by flipping a switch. Built in battery for portable use and fast charging. 3.5mm interface, compatible for PS3/TV/MP3/computer.