Master Tech Diesel Reman injector for GM LB7 Duramax 2001-2004. Master Tech Diesel injectors have a 2 Year Warranty. They are rebuilt with the highest quality parts and tested with the best calibration equipment available on the market. $150.00 refundable core charge due. We email you a separate paypal invoice for the core charge that will be refunded upon the return of the old used core.