I'm selling Rockford Fosgate 5 channel amp 600a5 for $500. I only used it for a week in my 98 528i. It's retail price of $830. 600a5 is new model for 1999. It has 50w*4+100w*1 at 4ohms. I'm selling it because it has too much bass and power for my speaker. I have original box and proof of purchase from manufacture.