1970-81 Camaro/Firebird Rear Hood Adjuster Screws and Bumpers. Accurate reproduction. Hardened bolts and jamb nuts with rubber bumpers provide adjustment for rear hood height and as a safety catch for hood hinges in the event of a hard front end crash. These bolts properly adjusted will lock into the hood hinges and keep the hood from the windshield. GM Part #: bolt, nut, bumper 3973952