DC Sports 4-1 Performance Header for the 03-07 Honda Accord is constructed from quality T-304, mandrel bent stainless steel piping and CNC machined flanges. Every header is tig welded by hand, both outside and inside of any joints. Larger than stock diameter piping, mandrel bends, and equal length primary runners insures a smooth and unrestricted path for exhaust gases. This leads to improved HP and TQ throughout your entire power band. Lastly, our header is fished off with a high gloss polished finish. Every DC Sports header is made to bold directly to all your OEM equipment, making the installation quick and easy.