Our weld-on, formed collectors are hand-crafted from 304 stainless steel or a low-carbon mild steel, and manufactured from 100% American made materials. The primaries are formed for ease of fitting. They have an overall length of 10". With such long lengths of straight, these collectors are easily trimmed by a fabricator to fit your vehicle needs. Don't forget to ask about collector stars or spikes to help in the fabrication process.