VERY Rare and powerful.. Hotshot all motor 2 piece race header w 2.5 collector..can b used on the street, but the down pipe has to be made for whatever application..coolness: match ported for zc will fit a d series also...4 into 1 design for max flow with equal length runners, the lower piece is 2 in now but can b cut to match 2.5 piping, great for high rpm $100 obo.