DFRobot Stereo Bluetooth Amplifier Board is a small size and cost-effective module with a volume adjustment function. The board connects to two speakers and matches a wide variety of high-power speakers (40W-200W). The Stereo Amplifier Board can be used as a small Bluetooth speaker when connected to Raspberry Pi or mobile phone. It offers excellent two-channel stereo sound effects. The board comes with power supply reverse connection protection, and short circuit protection. Note: Speakers sold separately.