The Bluetooth digital amplifier board uses two TPA3221 amplifier chips, which are high-performance, low-power, high-definition sound quality and comprehensive protection mechanism.The Bluetooth chip supports AAC and decoding. The large-area heat sink solves the heat dissipation problem and better utilizes the advantages of high power. Adding a power switch - .Lossless components - better sound quality. tuning of high and low frequencies - more convenient. The amplifier board has an onboard IPEX antenna interface, which can be connected to an external Bluetooth antenna (Bluetooth antenna not included). Different batches may have different appearances, which not affect the use; different light or display may cause color difference in the actual product NOTE: You need to assemble it yourself Colour:Black Material:PCB+Plastic+Metal Package Contents: 1 x Bluetooth Digital Amplifier Board 1 x case kit 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.