This is a DC single supply 12-24V supply, using TPA3116D2 high-performance digital amplifier chip as the core, parallel bridged channel amplifier, support 100W ( channel) output.External audio source input interface, with pre-amplification, crossover processing; volume, frequency, switch/ volume, 2 adjustment potentiometersWide operating voltage, -saving design, efficiency as high as 90%. You can use a switching supply with good performance, a laptop switching supply, a charging bottle, or a car 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 supply, and connect the audio input correctly, and it can be used.It has the characteristics of small size, high efficiency, high and small heat.Product SpecificationsName: Digital Amplifier Board amplifier chip: TPA3116Transmission distance: 10 meters (if you need a longer distance, please connect the external antenna yourself)Adapter supply: DC12-24V, 27A (can not be connected to AC)Protection mechanism: over temperature, over current, short circuit, anti-static protectioncolor: blueMaterial: PCBPackage Contents:1 * Amplifier board2 * hats1 set * screw1 * Audio cableOnly 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.