What's it for? The parts that say R&D look exactly like a 92 Kawi 650SX stock pipe but the part on the top left doesn't. It doesn't show the brand logo either, I'm trying to figure out how that pipe would fit into an SX engine compartment with that big curved stinger tail since the stock stinger is just a straight addition to the R&D part with the rubber coupler on it. The rest of looks like it would bolt up exactly like the stock SX pipe does though. It also looks like the small length of pipe on the curved expansion chamber was welded on afterward. It looks like a different type of stainless based on the color difference, plus the weld is a lot thicker than any of the other welds on the pipe, and the water injection fitting looks like a small piece of stainless tubing was welded on instead of an actual bard. It could be me not knowing exactly what I'm looking at, but I had a piece of stainless tubing welded onto the stinger for my 650SX and it looks exactly that way. The more I look at it, the more it looks like someone added that off color piece of tubing (for whatever reason) and cut off the part that would use the small rubber coupler for the head pipe. Here are a few pics of my pipe set-up, mostly stock, you can pretty well get the idea how the curved expansion chamber is held up by the small coupler even though you can't fully see it, I have no idea how that added on pipe would fit in there.