These are the necessary bumper mounting retainers that you MUST have for the installation of a new urethane front bumper. The Center Upper Front Bumper Retainer plays a mojor role in the way the Urethane Bumper sits on the Corvette. We strongly recommend that you DO NOT reuse your old retainers that might be rusted, bent or damaged. These GM stule retainer pieces will ensure the proper fit and look of your new 1975-1979 Corvette Urethane Front Bumper!