Features 1、[Multiple Input Methods] Supports multiple input methods including BT 5.1 connection, AUX input, U disk input, USB sound card and double channel microphone input, meeting various input needs. 2、[Wireless Connection] Supports MP3, mobile phone, computer, TV and other devices for wireless input, with fast connection response speed, smoothly running, no delay or lag in signal transfer. High decoding output, ensuring clear sound quality, restoring sound details. 3、[Knob Control] Using rotating encoder knob for 360° infinite tuning, supporting echo adjustment, subwoofer frequency adjustment, subwoofer volume adjustment, microphone volume adjustment, stereo high low note adjustment, and music volume adjustment. 4、[TPA3255 Chip] Equipped with TPA3255 amplifier chip and built in filter, providing pure sound with clear and transparent high note, soft and delicate mid note, and amazing low note effect. 5、[Multiple Conservation] Including reverse power connection, short circuit, self recovery overheat, etc., ensuring more reliable and stable use, and providing a safer experience for users. Specification Item Type: Power Amplifier Module Material: PCB Channel: 2.1 Channel (Left Channel, Right Channel, Subwoofer) Input Method: AUX, BT, USB Flash Drive, USB Sound Card (Knob to Switch Modes and Songs) Amplifier Chip: TPA3255 Compatible Speakers: Left and Right Channel 30-220W, 3-8Ω; Subwoofer 30-350W, 2-8Ω Adaptive Power Supply: DC 16-38V, ≥10A Conservation Mechanism: Reverse Connection, Under Voltage, Overheat, Overcurrent, Short Circuit Conservation (Automatically Recovered, No Need to Restart) Power Output: Left and Right Channel ≤220W, Subwoofer ≤350W Voltage Gain: 30dB Switch Mode: Mechanical Switch (No Need to Long Press and Wait) Size: Approx. 141x131x27mm / 5.55x5.16x1.06in Package List 1 x Top Cover 1 x Amplifier Module 5 x Knob Cap 1 x Bottom Cover 8 x M2x4 Screw 4 x M2x5+4 Copper Pillar 4 x M2x18 Copper Pillar 1 x Screwdriver