This is a DC single power supply 12-24V power supply, using TPA3116D2 high-performance digital power amplifier chip as the core, parallel bridged bass channel power amplifier, support 100W (bass channel) output. External audio source input interface, with pre-amplification, bass crossover processing; bass volume, bass frequency, switch/total volume, 2 adjustment potentiometers Wide operating voltage, power-saving design, efficiency as high as 90%. You can use a switching power supply with good performance, a laptop switching power supply, a charging bottle, or a car power supply, etc. The board is a finished board that has been welded and tested. Connect the speaker box according to the picture, connect the appropriate power supply, and connect the audio input correctly, and it can be used. It has the characteristics of small size, high efficiency, high power and small heat. Product Specifications Name: Digital Power Amplifier Board Power amplifier chip: TPA3116 Transmission distance: 10 meters (if you need a distance, please connect the external antenna yourself) Adapter power supply: DC12-24V, 27A (can not be connected to AC) Protection mechanism: over temperature, over current, short circuit, anti-static protection color: blue Material: PCB Package Contents: 1 * Amplifier board 2 * hats 1 set * screw 1 * Audio cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.