DROK 12V Digital Amplifier 2ch Audio Stereo Power Amp Board DC 11-14.5V Amplified Board with On/Off Switch DIY Car Headphone Audio Amplifier This is a dual-channel input and output digital amplifier with DC11-14.5V power supply. It has a high efficiency of 81%(25W, 4) and 88% (13.5W, 8), dynamic range is 100dB. RCA Plum commonly environmental-friendly transposon signal input, 4-wire signal output. It is equipped with power supply indicator which lights when turn it on, protection and turning on indicator. With speaker protaction and delay circuit while turning on, no impact when turn it on/off, can protect your speaker well.