6.6L diesel fuel injector nozzle. These are manufactured by D-Tech who has been supplying diesel parts for over 40 years to the diesel aftermarket. These items have been set to factory new specifications. If you are having injector problems such as white smoke, missing or low power, these nozzle tips make be the fix for you. They are easy to install and can have you back up and running in hours, not days. You do have to remove the injectors to perform this repair, so do not order if you do not feel comfortable removing your injectors from your engine.