Those are rivnuts or threadserts. Somebody added those in to mount something in the cars past. Those are not stock. They are prev owner installed. I have small bags of these things. Fantastic fasteners to have.
Those are rivnuts or threadserts. Somebody added those in to mount something in the cars past. Those are not stock. They are prev owner installed. I have small bags of these things. Fantastic fasteners to have.