This is a good used  fuel injector from a 1999-2003 7.3 Ford Powerstroke diesel engine. The number on top of the injector has 1831551C1 on it. It is also known as an "AD" injector.  We do not know the mileage of the injectors and have not been tested but are guaranteed for 30 days once received from UPS ground. The chart below will show the applications for this set of injectors. Please feel free to email or call us about this product if you have any questions at 713-676-2255 m-F 9-5 cdt.Stk# 36468