2-In-1 Design The Bluetooth adapter combines Bluetooth audio transmitter and receiver in one with an 3.5 mm Aux jack. Bluetooth connection is more stable and wireless range is more than 33 feet. Easy to pair and compatible with 99.9% Bluetooth devices. Updated Bluetooth 5.0 ensures strong signal transmission, low latency, high sound quality, less noice. Bluetooth Receivers When working as a Bluetooth receiver, it can still be paired to two smartphones or tablets, but the receiver can only receive the audio from one of the two paired devices. Please note that it only supports the codec of SBC when paired with two devices simultaneously. Bluetooth TransmitterWhen used as a Bluetooth transmitter, it can be paired to two Bluetooth receivers such as headphones and speakers simultaneously. In Transmitter mode, turn a non-Bluetooth TV, PC, CD player, iPod, MP3 / MP4 into Bluetooth transmitter. Receiver mode: Ideal for home or vehicle music streaming sound system. Low Delay & Long Battery Life Built-in 300 mAh polymer battery, it can work up to 8 hours when used as a receiver and up to 6 hours as a trasmitter. Enjoy superior stereo sound more with longer time compared to other brands at same price.