This is TDA7492p based is Class-D audio amplifier.  This module has integrated a Bluetooth module, all the used components in the amplifying process, output connectors and control buttons. All you need to do is supply 12V to 36A to it, connect an 8-ohm 50W speaker to each output and connect a Bluetooth device to it and enjoy and control your favourite music wirelessly.

In the layout above you can see that the board has 5 control buttons. You can also use those to change the track or control the volume. There is a DIP 2 switches button. Combining the up/down position of each switch you can obtain 4 different filters for the output. In the layout above you can see each combination and the applied gain in each case.

This Amplifier has Audio stereo input and connectivity to all versions of the Bluetooth connection, using CSR8635 Bluetooth chip with Bluetooth V4.0. Output Impedance of module is 8 ohms per channel. TDA7492 digital amplifier chip, designed to optimize the circuit layout, the sound quality is very good, big power DIP switches can be adjusted directly after the amp gain more respect and better promote greater damping horn.