Feature:1. Function Upgrade: In order to explore the maximum potential of this power amplifier board, we have developed an APP for this power amplifier board. You can adjust the sound effect of the power amplifier board through the APP, set the Bluetooth name and password of the power amplifier board, and even set whether a prompt tone is required.2. High Compatibility: The DC adapters on the market (plug size 5.5x2.1mm) can basically meet the needs of the Bluetooth power amplifier board. If your existing DC power plug is not 5.5x2.1mm, don't worry, because we include a DC conversion plug in the product.3. Bluetooth and AUX Input Mode: XY E30H has input memory function. If the power amplifier board was in AUX mode last time, this time the power amplifier board will be in AUX mode, and the same is true for Bluetooth mode.4. Treble and Bass Control: If you are tired of the original treble and bass, you can try the treble and bass control knob! No matter what, it can always help you to create the sound you like.5. Versatile Voltage Compatibility: The amplifier board supports a wide input voltage range from DC 9V to 24V, allowing it to be powered by 9‑V sources. This adaptability ensures that you can easily find a suitable power supply.Specification:Item Type: Bluetooth Power Amplifier BoardMaterial: PCB, Aluminum AlloySupply Voltage: 9‑24VBluetooth Version: 5.1Sound Channel: 2.1Sound Input: Bluetooth, AUXOutput Power: 15Wx2 (Left and Right Channel), 30W (Subwoofer).Package List:1 x Power Amplifier Board1 x Screwdriver1 x Wiring Terminal