The Pyle PFA400U 100 Watts Class-T Hi-Fi Stereo Amplifier is a class-T digital amplifier with up to 100 watts of power. Use it in your car, your boat, your RV, your golf cart, your home - anywhere you need a great amplifier with low distortion and acoustically accurate reproduction of music. Plus, the PFA400U is equipped with an SD card slot and USB port, so you can plug in a card or stick with your favorite MP3s already loaded. It is adjust the bass and treble to your liking, or bypass the included EQ. it takes 3.5mm stereo jack input stereo RCA and Â¬" microphone. It features 2-8 ohm speaker impedance compatible.