Bluetooth Transmitters features: 3 In 1 USB Bluetooth V5.0 Wireless Dongle Adapter Receive Transmit For TV/PC/Car Color: we send based on the color or size of the main image of the product page. Quantity：we send based on quantity on title, if there is no quantity in the title, we send based on description. Product specification: Bluetooth version: 5.0 + EDR Operating range: 10 m / 33 ft (no obstacles) Transmitter mode: Red LED on Receiver mode: Blue LED on Mode switch: click the button Product size: 45 * 20 * 9.5mm Net weight: 5g Gross weight: 15g Packaging accessories : 1 * Bluetooth 5.0 receiver transmitter Adapter 1 * AUX AUDIO CABLE 1 * Instruction manual Matching steps: This product is plug and play without driver A: Launch mode - red light 1. Plug the device into the USB port for power supply, switch to the transmission mode, and the red light will flash, and the Bluetooth device status (such as Bluetooth adapter, Bluetooth headset, Bluetooth speaker) will be automatically searched; 2. Insert one end of the 3.5mm audio cable into the aux interface of the adapter, and plug the other end into the audio output port of TV, projector, tablet computer, MP3 player, CD player and other equipment or RCA Audio signal output hole of TV; 3. Turn on the Bluetooth device and set it to the pairing state. If the pairing is successful, the red light is always on. Note: ① Computer plug and play, no drive, no connection (only audio can not transmit data). If there is no sound, please set the sound to sound card output in the sound settings. ② It is normal for different Bluetooth devices (such as Bluetooth headset) to search for connection time slightly due to the differences in scheme and protocol used. ③ If pairing fails or cannot be connected for a long time, you can turn off all devices and restart to pair again. B: Reception mode - blue light 1. Plug the device into the USB port for power supply, switch to the receiving mode, and the blue light flashes to enter the wireless receiving state (when the computer is powered on, plug the cable to the product first, and then plug the product into the computer); 2. Plug one end of the 3.5mm audio cable into the adapter aux interface, 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 the mobile phone or tablet computer, automatically search for Bluetooth devices, select "rt-09" in the Bluetooth list and click to pair. After successful pairing, the blue light is always on. Note: ① The device can also be directly inserted into the U-disk interface of the player to realize Bluetooth function. ② When there is no sound after successful connection, please delete the paired device. There may be Bluetooth device conflict.