major replacement part
(7) “major replacement part” means a major part that is— (A) an original major part in or on a completed motor vehicle and customized or modified after manufacture of the vehicle but before the time of its delivery to the first purchaser; or (B) not installed in or on a motor vehicle at the time of its delivery to the first purchaser and the equitable or legal title to the vehicle has not been transferred to a first purchaser.
49 USC § 33101(7)
None identified. Default scope is assumed to be the entire title.