2.1 channel Bluetooth power amplifier board with two 50 watt channels and a 100 watt sub output. This configuration provides clear stereo playback and amplified bass for a compact setup. AUX audio input and track wheel button. The track wheel button allows quick switching between modes and controlling playback, enabling convenient navigation through Aux, Bluetooth, and USB sources. USB input playback with output filtering for fidelity sound. The USB input supports playback with a built in filter to deliver hi fi, fidelity and definition sound quality. Easy to connect to your existing audio system. Designed for straightforward integration with your current speakers and setup. Use scenario 1: Upgrade a living room stereo by adding Bluetooth streaming and USB playback while preserving your existing speakers, for improved versatility and sound quality. Use scenario 2: Create a compact desktop or small room audio system. Use the AUX input for wired devices and Bluetooth or USB for convenient source switching, with enhanced 2.1 channel performance. Use scenario 3: DIY speaker project or hobby setup. The 2.1 channel arrangement and simple mode switching make it practical for custom builds that require multiple source options and amplified output.