car amplifier:RF-504J 1 RMS:50Wx4CH 2 Size:350x250x63mm 3 PCB single layer 4 terminal: bigger& better 5 Packing : color 6 heatsink black& blue paint car amplifier:RF-802J 1 RMS:80Wx2CH 2 Size:350x250x63mm 3 PCB single layer 4 terminal: bigger& better 5 Packing : color 6 heatsink red& black& blue paint As the professional manufacturer of car audio and video,we can provide these amplifier with surper quality and competitive price. Ifaany interests, please feel free to contact us, we will do our best to meet your demand.