Features: Experience exceptional sound with TPA3221 Amplifier Board. Its efficient and low distortions ensure a satisfying sound experience. Amplifier Board provides reliable protections features for worryfree usage. It includes reverse power input protections, overcurrent protections, and voltages protections. Power digital amplifier special inductors current, low magnetic loss, small heat generation. Use oxygen-freecopper wire to improve sound quality; magnetic shielded mechanism antielectromagnetic interferences Amplifier Board delivers impressive sound quality and immersively listenings experiences. It is perfect for music enthusiasts and home entertainment. Specifications: Product Name: 2.1 Channel Bluetooth-compatible Amplifier Board Power: 100W+100W+200W Model: ST21 Support TPA3221 Operating voltages DC12-30V Recommend voltages 24V-28V Current 10.0A/more than10.0A power Package：A: Without Housing/B: With Housing/C:External Leaded Type Package Includes: 1Set ST21 Bluetooth-compatible Amplifier Board note: Note: Shipment doesnot include power andaudio cable. Due to the problem of lighting effects and shooting there might be tolerances in the product, please understand. Please allow 0-2mm error due to manual measurment.