Description: This V4.2 audio receiver board is able to give your amplifier/home Stereo capability, just a very simple operation can be converted into Wireless audio, you won't need to be tethered by a cord when you Y play music through the AUX input on the home Stereo, from cord to say good-bye. Power: it's a Micro USB connection for power, powered by DC 5V, or if you want to solder your own power then you can take that route if you like the audio output connects to Headphones or active loudspeaker box or amplifier(if yours is passive loudspeaker box, please connect amplifier first) then your own Wireless audio is done. Super easy to connect the : open the function of your Cell phone or other devices with audio stream output support(such as laptops, tablet pcs, etc ), and then the phone will automatically search and pair with the module, No pairing codes or button mashing needed; effective transmission distance: 10-15 meters. It has three kinds of audio input: 1 receive; 2 USB Decoding play; 3 TF card Decoding play, press the " " Key to switch between them; support multiple formats: mp3, wma, wav, flac, ape; when you hook it up and turn your on and add your device then No one else can connect to it too so your building a homemade speaker box it's perfect, just enjoy your own DIY Wireless amplifier it. The audio transmitter board has small membrane buttons for , volume(volume can be controlled from the phone or buttons on the board), next, previous, play/stop and sound effect(only valid under USB or TF card ), please Refer to the pictures Shown on listing also has a small LED blinks Blue when. Specification: Audio input : 1. receiver 2. USB decoding play 3. TF card decoding play 4. FM radio (need to weld wire antenna by yourself)Supporting play format: MP3, WMA, WAV, FLAC , APE Package Includes: 1 x Amplifier Board 1 x Remote Control Note: - Remove the translucent white plastic sheet from the bottom of the control before using it, so to power on in the right way. - If you need the FM radio function, please first DIY a long wire as antenna on the FM antenna area. Key Operation: : press the " " button to switch among three kinds of audio input, receive USB decoding play TF card decoding play. NEXT: short press the "NEXT" button to play the next song, long press the "NEXT" button to increase volume. BACK: short press the "BACK" button to play the previous song, long press the "Back" button to decrease volume. EQ: sound effect manager(only valid under USB or TF card playing ). Audio Output: for connecting headphones, active loudspeaker box or amplifier(if yours is passive loudspeaker box, please connect amplifier first).