TheLisle Corporation 8-pc Injector Seal Installer Kit, No. 34720, is used for replacing teflon seals on most Hitachi, Bosch, Continental, and Delphi single and double sealed fuel injectors found on many Ford, GM, and Subaru engines. The pilot cone is placed onto the end of the injector and the seal is started over the cone. The installer is used to push the seal over the remainder of the cone and into the groove on the injector tip. Then the sizer is placed over the seal to compress it back to the correct OD to allow installation into the cylinder head.