1. Auto On When you connect to the power, So its very good for to use in car or other you want it have auto on functions. 2. Dual Device Link: Simultaneously pair your smartphone and tablet and stream music from either one with any stereo system that supports a standard 3.5mm or RCA jack.Connect two Bluetooth devices at once to listen to music, make phone calls, and more. 3. Connect two devices: Support to connect with 3.5mm audio port and 2 RCA audio port at the same time. 4. Wireless Music Streaming: Stereo stream music to non-Bluetooth headphones and speakers. 5. Space-Saving Design: Ultra-compact and lightweight for convenient use with a variety of devices. Super Stable Connection: Our Bluetooth audio adapter is fitted with a Bluetooth 5.0 chip for steady pairing, fast transmission and a wide signal range (33 feet). With the 3.5mm AUX port and 2 RCA port, it can be connected to non-Bluetooth car audio systems, home stereo, wired headphone/speaker, Amplifier/Home Theater.etc. Then you can enjoy wireless Hi-fi music streaming! Note: It's a vikefon Bluetooth receiver only, not a transmitter. So you couldn't use it for your TV, keyboard, mouse. Auto-Connect: This Bluetooth receiver will automatically connect to the last paired Bluetooth device when you turn it on the next time. Upgraded to support U Disk play. Note:No built in battery,So POWERED BY USB CHARGING. Colour:Black Material:Plastic Package Contents: 1 * Bluetooth Audio Receiver Adapter 1 * 3.5mm To Cable 1 * Type C Charging Cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.