SMAKN&reg; 20W+20W Class D digital amplifier board Mini amplifier board 12V-24V 100% Brand New and High Quality . The power amplifier module using American TL chip design company ,with undervoltage,overcurrent,output short circuit protection features perfect sound quality is supper good ! Set aside in the design of the shutdown control,mute control port, and has an output fault reporting output, more convenient secondary development appplication! Small Class D digital amplifier module . Two-channel stereo. Power supply voltage :8V-24V