[What chip does this power amplifier board use? ] This power amplifier board adopts two chips, wide voltage input DC: 12-36V, and the output power amplifier value can reach 160W x 2+220W (PMPO). [How many input modes?] This power amplifier board has three input modes, USB mode (USB flash memory mode and USB sound card mode), Bluetooth mode, and AUX mode. The priority of the input mode is the hardware priority principle. You can also switch its audio input source at any time through the APP. [Treble and Bass Controls!] If you are tired of the inherent treble and bass, why not try the treble and bass control knobs! No matter what, you can always create the sound you like. [Additional Features!]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 sound is required, etc. Color: black material: plastic Package Contents: 1 x Digital Amplifier Board 1 x Screwdriver 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.