Features 1.DIY audio conversion board support for Bluetooth wireless audio receiving, USB and TF card playback, AUX input, EO sound effects, etc. 2.You can upgrade your ordinary speakers or headphones to a high-end Bluetooth audio device with wireless music reception. 3.Suitable for Bluetooth 3.0/4.0 and 4.1 three-mode specifications. 4.Support HSP/HFP, support for Bluetooth hands-free calling function, voice communication and call report function. 5.Support for Android application communication through SPP protocol. 6.support for L2CAP/A2DP (AVCTP/AVDTP/AVRCP), control audio transmitter through protocol Up and down music operation. 7.Support simple pairing, support automatic connection back function, support low power mode sniff mode, stop mode. 8.With MP3 chip, it can support for TF card/U disk music playback, support WMA/MP3/WAV format decoding. 9.Support for EQ function: flat, rock, classical, jazz, etc. Specification Condition: 100% Brand New Item Type: Audio Receiver Board Interface: 1. Micro USB Charging Interface: 5V power supply (universal Android interface and USB mobile phone charger) 2. 3.5 Stereo Outlet: Designed For headphones with 16-64 ohm impedance, the bass is stronger and more powerful. 3. LOUT/ROUT Audio Output Socket: stereo left and right channel audio output designed for the audio impedance of the speaker in the camera 4. 3.5 Stereo AUX Input: Designed for 3.5mm stereo audio input AUX signal input (press MODE button to AUX mode) 5. INL/INR Audio Input Socket: Stereo left and right channel audio input designed for audio impedance when the speaker is modified in the machine 6. M+/M-Microphone Interface: Connect the microphone part, when the song is suddenly called, you can press the play button to answer the hands-free call. 7. ADKEY Button Expansion Port: Simple 2-wire button socket, easy to expand according to the provided line and resistance parameter links 8. GND/+5V Solder Joint: The Internal modification is the solder joint of the 5V power input 9. USB Interface: Decode and Play the WMA/MP3/WAV music format file on the U disk, and support up to 64G USB flash drive. 10. TF Card Interface: Decode the WMA/MP3/WAV music format file on the TF storage, and support up to 32G capacity card. Button: 1. MODE Function Mode Button: Short press the button to cycle through the "Bluetooth 1> AUX->USB->TF" several function modes 2. PLAY Play Pause Button: Short Press play/pause/answer call 3. NEXT Song Plus / Volume Plus Button: short press the next song, long press the volume to increase 4. PREV Song Plus / Volume Down Button: short press the previous song, long press the volume to decrease 5. EQ Sound Button: When playing USB and TF card music, short press with flat, rock, classical, jazz and other audio output Package List 1 x Audio Receiver Board 2 x 3-pin Connector 2 x 2-pin Connector 1 x Audio Receiver Connector