This digital power amplifier board with high fidelity and two-channel stereo sound quality; input voltage is DC 12~30V, audio input supports Bluetooth, TF card, AUX 3.5mm audio line input, can be directly connected to mobile phone, MP3, etc.; power amplifier board It also comes with a volume adjustment function, which rotates the chirp potentiometer clockwise to zoom in and counterclockwise to decrease.Product Name: Two-channel Bluetooth 5.0 power amplifier boardInput voltage: DC12-30VAmp Chip:TDA7498Output impedance:4~8 ohm SpeakerSupport Format:FLAC/APE/MP3/WMA/WAVCurrent: 3AOutput power: 100W*2Audio input: Bluetooth, TF card, AUXNumber of channels: two channelsSize: 92*85*10MMInstallation aperture: 3MMInstallation hole distance: 85*5*78.5MMBluetooth operation instructions:When the power amplifier board is connected to the power supply and the Bluetooth is not connected, the Bluetooth indicator will flash rapidly. When the Bluetooth connection is successful, the Bluetooth indicator will stop flashing. When the song is played, the Bluetooth indicator will flash slowly.Note:1. Connect the power input to the DC12-30V power supply. When the power is on, the power indicator will light red and the blue light will flash blue.2. Connect the audio input to the audio source, such as MP3, mobile phone, computer, TF card, etc.3. Connect the audio output to the speaker, paying attention to the positive and negative.Bluetooth / TF card volume hole:When the audio input uses Bluetooth or TF card, you can connect the power cord to the "+ VOL -" three holes to adjust the volume and switch songs.1. "+" and "VOL" connection: short connection to play the previous song, long connection to increase the volume2. "-" and "VOL" connection: short connection to play the next song, long connection to reduce the volume