[ upgrade] The Bluetooth 5.0 power amplifier board supports APP control, and you can modify the Bluetooth name and password settings. The 5.0 Bluetooth version has settings such as adjustable sound volume, turn on/off sound, and timed shutdown. Comes with 10 natural sleep songs, up to 1023 sound combinations. Not only can you display the playlist of the USB flash drive, but you can also shake the phone to change songs or use the dial/mode button to switch songs [TPA3116D2 power amplifier chip] The power amplifier board uses TPA3116D2 chips from . It is a high-performance class D power amplifier, which has class D efficiency and can bring true high-end sound quality. The device features an advanced integrated feedback design and proprietary high-speed gate driver error correction. This technology enables the device to maintain ultra-low distortion across the entire audio frequency band while delivering high-definition sound quality [Super Compatibility] 5.0 Bluetooth 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, , smartphones, notebook computers, etc [Safety Protection] The amplifier board 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 Color:As Shown Material:PCB Package Contents: 1 * Amplifier board 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.