Cat C13 LEE . This file is meant to be used to keep all the parts intact. The ARD head has an exhaust temp sensor included in it. This file requires the use of the exhaust temp sensor. These are around 470 hp and 1700 tq. I have several trucks that I have been running these files in for several years now and they work great. Includes instructions for settings in parameters plus Im always available for questions. I will send you a link thru ebay messaging. Paste it to google and it will auto download. Go to your downloads and right click it and unzip it with winzip or 7zip. Thanks!