[HIFI & Stereo]High-quality Bluetooth 5.1 dual-channel 50W+50W power amplifier board. With AUX, Bluetooth, U disk, USB sound card a variety of audio input methods. Active and passive speaker output methods. Note: It is recommended to use a 18V19V power supply with a current of more than 3A. It is not recommended to use 24V and above, it may be burned due to unstable power supply, depending on the quality of the power supply. If driving 4Ω speakers, the power supply must not exceed 21V [Ultra high performance]Mini amplifier board supports APP control, you can modify the Bluetooth name and password settings. The 5.1 Bluetooth version has adjustable prompt tone volume, power on and off prompt tone, volume indication is synchronized with APP, and 8-level brightness can be adjusted. Comes with 10 custom sound effects, up to 1023 sound combinations. It can not only display the playlist of the U disk, but also shake the phone to change songs to choose at will [Super Compatibility]Bluetooth 5.1 amplifier version, higher transmission efficiency, more stable, and longer transmission distance. In open spaces, the wireless range is up to 15 meters (49 feet). Can be widely used in various devices such as tablet computers, PCs, TVs, smartphones, notebook computers, etc [Safety Protection]The amplifier module has short circuit, overcurrent, overheating and anti-static protection to prevent complete failure. When overloaded, the device reports a fault condition to the processor to protect itself from damage. The heat sink is close to the shell to assist heat dissipation, the bottom ventilation is not sealed, the heat dissipation area is larger, and the heat dissipation is more sufficient [Easy operation] 360-degree rotation to adjust the volume steplessly, cool volume level indication, 8-level brightness selection. Press and hold for 1 second to turn on/off, click to play/pause, double-click to switch modes (Bluetooth/USB/AUX) color:Photo color Material:plastic Package Contents: 1 x Amplifier board 1 x Screwdriver 1 x DC adapter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.