Product Specifications: Model: SY319 Bluetooth version: 5.0+EDR Operating range: 10 m /33 ft Max (no obstructions) Emitter mode: red LED light on Receiver mode: blue LED lights on Mode toggle: click the button Product size: 45*20*9.5mm Net weight: 5g Gross weight: 15g Matching steps: This product is plug and play, no driver required A: Launch mode - red light 1. Plug the device into the USB port for power supply, switch to the transmitting mode and the red light flashes, and enter the state of automatic search for Bluetooth devices (such as Bluetooth adapter, Bluetooth headset, Bluetooth speaker); 2. Insert one end of the 3.5mm audio cable into the AUX interface of the adapter, and the other end into the audio Output hole of the TV, projector, tablet computer, MP3, CD player and other equipment or the RCA audio signal Output hole of the TV; 3. Turn the Bluetooth device on and set it to the pairing state. The pairing is successful, and the red light is always on. Note: The computer plug and play, no drive, no connection (only audio can not transmit data).If there is no sound, set the sound to sound card output in the sound Settings. (2) Different Bluetooth devices (such as Bluetooth headset) due to the use of the scheme and protocol differences, search connection time is slightly different, is normal. (3) If the pairing fails or cannot be connected for a long time, you can turn off all devices and restart the pairing again. B: Receiving mode - blue light 1. Plug the device into the USB port for power supply, switch to the receiving mode, the blue light flashes, and enter the wireless receiving state (when the computer is powered, first plug the wire into the product, and then plug the product into the computer); 2. Insert one end of the 3.5mm audio cable into the AUX interface of the adapter, and the other end into the audio input interface of the playback device (such as: headphones, speakers, cars, etc.), or plug the 3.5 audio cable of other playback devices into the audio port of the device. 3. Turn on the Bluetooth function of mobile phone or tablet, automatically search for Bluetooth devices, selectRT-09"in the Bluetooth list and clickPairing. The blue light is always on after successful pairing. Note: The Bluetooth function can also be realized by directly inserting the device into the U disk reading interface of the player. When the connection is successful and no sound occurs, please delete the device that has been paired successfully. There may be Bluetooth device conflict. Packing accessories: 1* 5.0 Bluetooth receiver transmitter 1* AUX audio cable 1* English and Chinese manual