2 in 1 Bluetooth Transmitter and Receiver: UGREEN 3.5mm wireless adapter supports both Bluetooth transmitting and receiving, namely TX and RX Mode. ( Note: Phone calls only be supported in RX mode, not in TX mode). The aux bluetooth transmitter allows you to transform the non-Bluetooth stereo devices (including TVs, PCs, home theaters, car stereos) to Bluetooth enabled devices. Just connect the Bluetooth converter to your old devices and enjoy the high-quality sound from wireless speakers. Stable Connection: With Bluetooth 5.0 technology, UGREEN bluetooth transmitter would reduce power consumption and offer a fast and stable transmission. The playtime of the wireless 3.5mm bluetooth transmitter is up to 5.5 hours in RX mode and 8 hours in TX mode. Additionally, the Aux connector can be paired to two Bluetooth devices at the same time in both RX and TX mode. Easy to Use: According to its status indicators, the bluetooth transmitter for headphones is quite easy to install and use. Just insert the Bluetooth 5.0 adapter into the AUX port of Bluetooth receiver or transmitter, then press and hold the multifunction button for 3 seconds to power on and ready for pairing. The adapter will automatically pair with and connect to your devices. Wide Compatibility: This 2 in 1 Wireless 3.5mm Bluetooth Adapter is compatible with devices of 3.5mm interface, including TV, car stereos, home stereo system, headphones, audio music streaming sound system, PC, speakers, projector, MP3, MP4 etc. (Note: Not compatible with AirPods Pro 2) Compact and Portable: Ultra compact design of this 1/8 Bluetooth transmitter and receiver would save your space. You can easily carry this Aux Bluetooth adapter around and everywhere easily without any hassle as its portable size and lightweight design.