Digital Amplifier Board, DROK Audio Amp Module DC 12V~24V TPA3123 Class D 50W Subwoofer 25W+25W 2.1 Channel Stereo Power Amplify Chip for Audio System DIY Speakers This amplifier board with 2*TPA3123 digital amplifier chip, one for left and right channel power amplifier, one for bridge driver subwoofer, Left and right channel output 20W*2, subwoofer output 40W, efficiency can reach above 90%, small size, efficient, high-power. can use laptop switching power supply or battery-powered devices, such as motorcycles, cars, electric cars and etc. Powered: DC 12V-24V (voltage suggested: 15V-20V, high-quality switching power supply) Maximum output: left and right channel 25W*2, subwoofer 50W Size: 82mm * 65mm