This power amplifier is compact, easy to carry, and simple to use, dual channel stereo sound, without compromising sound quality. Features: Stepless tuning, smooth feel, one button start/stop. It can be controlled through the mobilephone app, making the operation more convenient and quick. Fine sound quality. Comapct size for easy carrying. Power reverse connection protections, short circuit protections, self recovery overheat protections. Specifications: Main color: black BT: 5.0 Transmission distance: 15m Adaptation speaker: 0-200W 4 8 16 Output power: 50W*2 Item size: 75 * 50 * 18mm / 3.0 * 2.0 * 0.7in Package size: 115 * 60 * 35mm / 4.5 * 2.4 * 1.4in Package weight: 61g / 2.2ounce Packing List: 1 * Power Amplifier 1 * Heat Sink 1 * Adapter