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 a switching supply with good performance, a laptop switching supply, a charging bottle, or a car supply, etc.The board is a finished board has been welded and tested. the speaker box according to the , the appropriate supply, and 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 distance, please 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 the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.