Features: Receive & Transmitone Key Switch: Receive (Rx) signal and transmit (TX) signal are integrated.Free switching applicable to a variety of devices. Receiving Mode: Audio playback device connected with speakers to receive. Bluetooth-compatible signals and play music wirelessly. Launch Mode: Connect the audio output device transmit the Bluetooth-compatible signal and use the paired wireless headset Bluetooth-compatible audio playing music.Solve the problem that the TV cannot connect to the Bluetooth-compatible headset. Watching TV at night is not afraid to disturb your family. Receive Mode Onboard Connection: The car speaker changes into a Bluetooth-compatible speaker in seconds plug and play and automatically connects back. Enjoy mobile music and HD voice navigation broadcast. Hands-Free Call & Built-in Microphone: Hands-Free communication hands on the steering wheel safer driving. Connect ordinary speakers break space restrictions and enjoy wireless convenience. Stereoscopic amplification shocking sound effect. Notice: Actual color may be slightly different from the image due to different display and light effect. Please allow 1-3cm deviation due to manual measurement. Specifications: Working time: 8h for receiving and 5h for transmitting Bluetooth-compatible version: 5.1 Frequency response: 10HZ to 2HKZ Signal to noise ratio: Less than 110dB Connection range: 15m Product function: Receive+transmit+handsfree call Battery capacity: 150mAh Product size: 70.8 * 20.5 * 11.5 mm includes: Machine *1 Charging cable*1 Manual *1 "