Feature: 1. This portable, lightweight wireless audio transmitter and receiver is the ideal wireless audio solution for every situation and application 2. Transmitter mode: wirelessly transmits audio from non-Bluetooth TVs, home stereo systems, or CD players to Bluetooth headsets or speakers. 3. Receiver mode: wirelessly transmits audio from Bluetooth-enabled mobile phones, tablets, or computers to cable, speakers, or headphones. 4. Mode switching: A)First plug the product into the USB port to power up. B)When powered on, the default mode of the machine is the transmitter mode. C)Press and hold the side button for more than 3 seconds to switch to receiver mode. Press and hold to switch back to the transmitter mode. 5. Pairing and using methods A）Receive mode usage methods: Blue LED flashes to indicate that it has switched to receive mode. The USB of this product is used for power supply and can be plugged into any USB interface with 5V output. For example, a mobile phone charger. Find the pairing name of the BT 600 in the Bluetooth settings of your phone. The paired successful Bluetooth light will be on. Play audio files on your phone, and use the 3.5 headphone cable to connect to speakers, car audio, and other Bluetooth-free devices. You can also plug in the 3.5 headphone port with a wired headset to listen to music. B）to receive mode. The USB of this product is used for power supply and can be plugged into any USB interface with a 5V output. For example, a mobile phone charger. Find the pairing name of the BT 600 in the Bluetooth settings of your phone. The paired successful Bluetooth light will be on. Play audio files in your phone, and use the 3.5 headphone cable to connect to speakers, car audio, and other Bluetooth-free devices. You can also plug in the 3.5 headphone port with a wired headset to listen to music. 6. The unit is small and exquisite but has powerful transmitting and receiving functions, which are convenient to carry. 7. Wide compatibility. This product is widely used in your computer/pen computer/home stereo system /headset / smartphone / MP3 player /CD player. Specification: Interface: USB.3.5 Plug and Play: Plug and Play External power supply: No external power supply. Transmission rate: 100(Mbps) Effective working radius: 10(m) Bluetooth standard: 5.2 Operating frequency: 2400(MHz) Package List： 1xBluetooth 5.3 Adapter 1xUser Manual