It is a National Hot Rod Association class for drag racing. (I used to run A/Gas and A/Gas supercharged). But seriously, it is a product that has been returned to the manufacturer after being received DOA, dealer coudn't pay his bill, dealer dropped the line, etc. It is usually not a damaged piece. It IS USUALLY a very good deal. HCM sells a lot of B-stock gear at great prices. I am using a $2200 amp which I bought from HCM as B-stock for $899 many years ago. Never had slightest problem with it. Don