These are a rebuilt set of 8 Bosch Design III Fuel Injectors. If your car came with anything but 24's the ECU will need recalibration. These are stock replacements for 1985 L98, 1994-96 LT1 and 97 and up LS1These injectors have the same installed height as the stock GM multec, please specify if you are buying these for the LS1 as the orings are differentThree year warrantyPart Number: FIC24REBUILT